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FACTORS AFFECTING PRODUCTION AND QUALITY
IN CONSTRUCTION INDUSTRY
Chukwuji Christian F.M
PG/M.Engr/09/50669
FACTORS AFFECTING PRODUCTION AND QUALITY
IN CONSTRUCTION INDUSTRY
Department of Civil Engineering
Engineering
Okey ijere
Digitally Signed by: Content manager’s Name DN : CN = Webmaster’s name O= University of Nigeria, Nsukka OU = Innovation Centre
ii
A Dissertation Report by
Chukwuji Christian F.M
PG/M.Engr/09/50669
Department of Civil Engineering
Postgraduate School
University of Nigeria Nsukka
In Partial Fulfillment of the Requirement for the Award of
Master of Engineering Degree in Materials and Construction
Engineering
March, 2012
iii
APPROVAL
This research study has been approved by the supervisor Engr. Prof. O.O.Ugwu
and the Department of Civil Engineering, for Chukwuji Christian. F.M. with
registration number PG/MEng/09/50669
…………………………………………….. ………………………
Engr Prof O.O.Ugwu Date
Supervisor
……………………………………………. ………………………
Engr. J.C. Ezeokonkwo Date
HOD. Department of Civil Engineering
…………………………………………….. ….….…………………
Prof J. C. Agunwamba Date
Dean Faculty of Engineering
iv
CERTIFICATION
Chukwuji Christian F.M. of Department of Civil Engineering with registration
NO.PG/MEng/09/50669 has satisfactorily completed this research report in partial
fulfillment of the requirement for the award of Master of Engineering in Materials
and Construction Engineering. This report is his original research study and has not
been submitted in part or complete for any other certificate of other universities or
similar institutions
…………………………………………….. ………………………
Engr Prof O.O.Ugwu Date
Supervisor
……………………………………………. ………………………
Engr. J.C. Ezeokonkwo Date
HOD. Department of Civil Engineering
…………………………………………….. ….….…………………
Prof J. C. Agunwamba Date
Dean Faculty of Engineering
DEDICATION
v
This research study is dedicated to the glory of Almighty God and to every lover of
the civil engineering profession
ACKNOWLEDGEMENT
vi
I acknowledge with thanks my academic and professional colleagues, who in one
way or the other assisted me in carrying out this research study. My special thanks
goes to my supervisor Engr. Professor O. O. Ugwu for his scholarly guidance
throughout the study.
I express my gratitude to all the managers and supervisors of selected indigenous
construction companies in Akwa-Ibom, Bauchi, Benue, Enugu, Kaduna, Oyo, and
Abuja FTC respectively, who with ease gave me the information that I needed for
this research.
I am equally grateful to Misses Charity Diugwu and Blessing Iro who
painstakingly typed this dissertation report.
vii
ABSRACT
This research was conducted to appraise the factors affecting construction workers
productivity and quality of work in indigenous construction companies in Nigeria.
The observed low productivity, shoddy work and poor finishing by craft workers
employed in these companies inspired the choice of the research topic. The
objective of this research was to ascertain if the managers of construction
companies actually use modern planning methods and adequate motivation in
managing construction workers for high productivity. It also aimed at verifying
whether the indigenous construction companies employ qualify and trained craft
workers that will ensure quality of their work. The research investigated the
productivity and quality problems using field survey method. The survey adopted
closed form structured questionnaires distributed to construction managers, site
engineers, and supervisors of these companies. Seventy randomly selected
indigenous construction companies in the six geo-political zones of the federation
were given the questionnaires and fifty-two returned their filled questionnaires.
The field data collected from the companies were analyzed and tested by non-
parametric statistics method of frequency, percentage, ranking and chi-square at
5% level of significance. The research findings and results further confirmed that
the problems of low productivity and poor quality of work observed in indigenous
construction companies was due to improper planning of workforce, non-
motivation and inadequate training of craft workers. Based on the results, and
analysis of the field survey, fifteen-decision models were recommended to help the
indigenous construction companies solve the problems of low productivity and
poor quality of work.
viii
TABLE OF CONTENTS
Title page … … … … … …. …. … i
Approval … … … … … …. …. … ii
Certification … … … … … …. …. … iii
Dedication … … … … … …. …. … iv
Acknowledgment … … … … … …. …. … v
Abstract … … … … … …. …. … vi
Table of content … … … … … …. …. … vii
List of tables … … … … … …. …. … ix
List of figures … … … … … …. …. … xii
Definition of terms … … … … … …. …. … xii CHAPTER ONE: INTRODUCTION
1.1 Background to the study … … … … … …. 1
1.2 Statement of problem … … … … … …. 3
1.3 Research questions … … … … … …. …. 3
1.4 Aim and objectives of study … … … … … 4
1.5 Hypothesis … … … … … …. …. … 4
1.6 Significance of study … … … … … …. …. 5
1.7 Scope and delimitation … … … … … …. 5
CHAPTER TWO: LITERATURE REVIEW
2.1 Trade classification of construction workers … … … 7
2.2 Craft workers Job and Work Standard … … … … 7
2.3 Work force planning and supervision … … …… … … 9
2.4 Productivity control of work force … … …… … … 26
ix
2.5 Productivity motivation of construction workers … … … 30
2.6 Effective communication on construction site… … … 32
2.7 Quality control of construction resources… … …… … 34
2.8 Education and training of craftsmen … … …… … 49
CHAPTER THREE: METHODOLOGY
3.1 Research design … … …… … …… … …… … 62
3.2 Scope of study … … …… … …… … …… 62
3.3 Population of study … … …… … …… … 62
3.4 Sample and sampling technique … … …… … 62
3.5 Instrument of data collection … … …… … …… 63
3.6 Validation of Instrument … … …… … …… 63
3.7 Method of data collection … … …… … …… 63
3.8 Method of data analysis … … …… … …… 63
3.9 Statistical presentation of data … … …… … …… 63
3.10 Analysis of data … … …… … …… … …… 76
CHAPTER FOUR: RESULTS AND DISCUSSION OF FINDINGS
4.1Results of field Survey … … … …… … …… 86
4.2 Discussion of Results … … …… … …… … 87
CHAPTER FIVE: CONCLUSION AND RECOMMENDATION
5.1 Conclusion … … …… … …… … …… … 89
5.2 Recommendation … … …… … …… … …… 90
5.3 Limitations of study… … …… … …… … …… 91 REFERENCES
APPENDICES
x
List of tables
Table 2.1 A Typical Workers Output Standard,
Table 2.2 A Typical Man-Hour Output and Cost Contribution of Craft Workers in
a Construction Project.
Table 2.2 Work Programme lot 2: Construction Of 2nd 6km Length + 4 Culverts
Dual Road Construction
Table 2.3: A Monthly Workforce Schedule for a Typical Building Project.
Table 2.2 Work Programme for the construction of 2nd 6km Length + 4 Culverts
dual road
Table 2.3: A Monthly Workforce Schedule for a Typical Building Project.
Table 2.4 Work Instruction Form
Table2.5 Setting out Checklist
Table 2.6 Strip Foundation Checklist
Table 2.7 Piling Checklist
Table 2.8 Pile cap/Ground beam Checklist
Table 2.4 Work Instruction Form
Table2.5 Setting out Checklist
Table 2.6 Strip Foundation Checklist
Table 2.7 Piling Checklist
Table 2.8 Pile cap/Ground beam Checklist
Table 2.9: A typical Labour Time Card for Craftsmen
Table2.10 Foreman’s Daily Labour Report
Table 2.11 Construction manager weekly labour productivity report Chart.
Table 2.12 Frequency of Inspection and Tolerances in Workmanship
Table 2.13 Frequency of tests for quality control on Road Construction
Table 2.14: Standard normal variable associated with various confidence levels
Table 2.15 Typical Inspection Measuring and Testing Equipment on Building Site
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Table 2.16 (A) Internal Quality Audit Form.
Table 2.16 (b) Internal Quality Audit Form
Table 3.1: Questionnaire No 1; Ownership composition of your company
Table 3.2: Questionnaire No 2; Area of specialization of your company
Table 3.3: Questionnaire No3; Age of your company in construction
Table 3.4: Questionnaire No 4; Category of registration of your company.
Table 3.5: Questionnaire No 5; Geographical location of your company
Table 3.6 Questionnaire No 6; What is the employment status of greater number of
your craft workers.
Table 3.7: Questionnaire No 7; What is your company’s project planning set up.
Table 3.8 Questionnaire No 8; Who is the head of project planning in your
company.
Table 3.9 Questionnaire No 9; What type of construction planning method is
adopted in your company.
Table 3.10: Questionnaire No 10; With regard to your present construction
planning method, estimate crafts workers output in your company.
Table 3.11: Questionnaire No 11; If the output of your craft workers is below
average what is the anticipated cause(s).
Table 3.12: Questionnaire No 12;What type of quality control method is adopted in
your company
Table 3.13: Questionnaire No 13; Please estimate your craftsmen quality of work
with your present method of quality control
Table 3.14: Questionnaire No 14: If the quality of work is below average, what
could be the cause(s)
Table 3.15 Quetionnaire15; What method have you been using to determine the
output of your craftsmen
xii
Table 3.16 Questionnaire No 16; Please indicate the ratio of staff and casual
craftsmen in your company
Table 3.17: Questionnaire No 17; What is the monthly salary for a staff craftsman
in your company
Table 3.18: Questionnaire No 18; What is the daily wage for a casual craftsman
employed in your company
Table 3.19: Questionnaire No19; What Incentive packages have you adopted for
your craft workers
Table 3.20: Questionnaire No 20; Please with the present wages, salaries and
incentive packages paid by your company estimate craft workers output
Table 3.21: Questionnaire No 21; If the output of craft workers is still below
average, what is the anticipated cause(s).
Table 3.22: Questionnaires No 22: What is your recruitment source(s) for craft
workers.
Table 3.23: Questionnaire No 23; What is the minimum qualification for your craft
workers.
Table 3.24: Questionnaire No 24: What is your training or retraining scheme for
craftsmen in your company.
Table 3.25: Questionnaire 25; With the present level of qualification and training
of your craftsmen estimate their efficiency in terms of output and quality of work
Table 3.26 Analysis of data
Table 3.27 Analysis of data
Table 3.28 Analysis of data
Table 3.29 Analysis of data
Table 3.30 Testing of hypotheses 1
Table 3.31 Analysis of data
Table 3.32 Testing of hypotheses 2
xiii
Table 3.33 Analysis of data
Table 3.34 Testing of hypotheses 3
Lists of figures
Figs 2.1 Dual Road Construction Critical Path Network
Fig. 2.2 A typical work grouping chart (section)
Fig. 2.3 Labour Accounting System
Fig. 2.4: Site Communication chart
Fig. 2.5: Normal distribution curve.
Fig. 2.6: Standard normal density curve
Fig 3.1 Graphical analysis of data
Fig 3.2 Graphical analysis of data
Fig 3.3 Graphical analysis of data
Fig 3.4 Graphical analysis of data
Fig 3.5 Graphical analysis of data
Fig 3.6 Graphical analysis of data
Definition of Terms
i. Productivity - is the ratio of output to input.
ii. Worker’s productivity - implies the quantity of work done per man-hour.
iii. Workers productivity standard – is the effort in man-hour needed to
accomplish a unit quantity of work, while working efficiently but allowing
for normal delays and wastage.
iv. Productivity efficiency factor - is the multiplier used to convert production
norms into productivity standard expected under job condition on site.
v. Craftsmen – refers to skilled workers, craft workers or tradesmen working in
building or civil engineering companies.
xiv
vi. Indigenous construction companies – means local construction companies
fully owned and managed by Nigerians
vii Multinational construction companies - means Nigerian registered
construction companies owned and managed by 70% foreigners and 30%
Nigerians
viii Productivity control – is the monitoring of performance and applying
corrective measures in case of deviation from plan
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CHAPTER ONE: INTRODUCTION
1.1 Background of the study
Productivity at both micro and macro -economic level is a serious issue as far as
the industrial sector is concerned. Construction industry is definitely one of such
industries that make very high economic contributions in every nation. The
industry usually accounts for, between 6-9% of Gross Domestic Product (GDP)
and over 50% fixed capital formation of both developed and developing nations of
the world, (Chitkara, 2006).
Jeremaih (2012) in Federal Radio Corporation of Nigeria (FRCN) documentary
report wrote “Productivity data is the source of real economic growth and major
determinant of a nation’s living standard. A single challenge to many societies is
therefore, how to create a condition for rapid and sustained productivity growth
especially at organizational and industrial levels. It is in realization of the
important role of productivity that many nations of the world have established
National Productivity Organizations (NPOs) as part of the strategies to promote
productivity in individual enterprises and nations. The primary duty of every NPO
is to provide an improved quality of life of the citizenry, promote productivity and
competitiveness. It is in view of the poor productivity growth in Africa that Heads
of States of countries in African Union, at the 16th Ordinary Session, requested
member states to accelerate the implementation of the productivity agenda for
African, which include the establishment of NPOs in each member states. In
Nigeria, the National Productivity Centre (NPC) was established in 2004 and given
the responsibility to research on the productivity of all sector of the economy,
under the supervision of Federal Ministry of Labour and Productivity. Its mandate
include, to formulate and advice on productivity policy that will guide all sectors
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of the economy, design and initiate productivity and quality programmes, annual
productivity measurement criteria, and provide a reliable data bank on productivity
growth of the country etc”.
Construction is a creative and developmental venture. In view of these facts more
emphasis is placed on the productivity and quality of work produced by
construction workers. Incidentally, in the past three decades, after the oil boom of
1970s, the construction industry in Nigeria has been facing serious problem of low
productivity. A case study once indicated that except in Lagos and Abuja the
former and new capital territories of Nigeria respectively, construction workers
have performed poorly in every other state of the federation. The disparity may be
deduced from the efficiency of the multinational construction companies operating
in the two territories. Also, when compared with the manufacturing sector, it was
easy to observe that the productivity problem is more in the construction industry
than in the manufacturing industry, which has continued to report rise in
productivity for nearly two decades now.
Productivity is actually the measure of individual or collective performance of
resource(s) input in an organization or an enterprise. The construction industry
resources are, men, materials, machines and money. Of these resources, the most
vulnerable and grossly mismanaged in the Nigerian construction industry is the
men or construction workers. The present craftsmen, who constitute about 60% of
the direct construction workers in every project site, have not shown marked
improvement in their performance since the exit of master craftsmen in 1970s. The
situation could not be remedied by influx of craftsmen from neighboring countries
of Ghana and Bene Republic.
3
Many genuine investors, developers, designers, and construction managers, have
continued to indicate their serious concern on the low output and poor quality of
work of this generation of craftsmen, especially on construction projects executed
by indigenous contractors. They fear that the continuous decrease in productivity
and quality of work by the present crop of construction craftsmen will eventually
cripple the industry and its GDP coupled with the current rate of building collapse
and road failures. However, it is believed that certain factors are critically
responsible for the low productivity and poor quality of work of Nigerian
craftsmen employed in indigenous companies. These factors formed the basis of
this project study.
1.2 Statement of Problem
Construction craft workers’ low productivity and poor quality of work in Nigeria
as professionals have continuously indicated result from many factors. These
limiting factors range from improper planning and control, inadequate training,
lack of motivation, poor welfare management, complexity of work, unavailability
of materials, malnutrition, poor leadership, sickness, absenteeism, labour turnover,
poor communication and supervision, adverse environmental and climatic
conditions etc. All these factors exert varying degrees of limitations and influence
on the output of the craftsmen. In this research, the most critical factors affecting
the productivity and quality of work of these craftsmen employed in Nigerian
indigenous construction companies were investigated.
1.3 Research Questions
i. Can improper planning and poor supervision greatly affect the productivity of
construction workers in our indigenous construction companies?
4
ii. Can poor wages and absent of motivational incentives significantly affect the
productivity of construction workers in indigenous construction companies?
iii. Will inadequate education and vocational training greatly affect the quality of
work and output of craft workers in indigenous construction companies?
1.4 Aim and Objectives of Study
The aim of this study is to appraise the three major factors affecting the
productivity and quality of work or otherwise of the craft workers employed in
indigenous construction companies in Nigeria. To achieve this, the following
objectives have been set out:
i. To ascertain whether the construction managers of our indigenous
construction companies have adequate knowledge and application of the
modern planning, supervision and control techniques on labour workforce on
project sites that will ensure higher productivity.
ii. To ascertain how often or otherwise the managers use incentives to motivate
craft workers for higher productivity.
iii. To verify if the present level of education and training of craftsmen employed
in the indigenous construction firms is adequate to ensure quality of work and
high productivity.
1.5 Hypothesis
H01: Improper planning, supervision and control of craft workers activities on
construction site significantly affect their productivity and quality of work in
indigenous construction companies in Nigeria.
H02: Poor wages and inadequate motivational incentives significantly affect the
productivity and quality of work of craft workers in indigenous construction
firms in Nigeria.
5
H03: Inadequate education and vocational training of craft workers significantly
affect their quality of work in indigenous construction companies in Nigeria.
1.6 Significance of Study
i. The completed study will highlight the importance for managers of the
indigenous construction companies to continually apply modern planning,
supervision and control techniques in the management of craft work force for
higher productivity.
ii. The study will intimate indigenous contractors the relevance of training and
retraining of craftsmen as a sure way to increase their productivity and quality
of work.
iii. It will give credence to the success associated with adequate incentives
packages to motivate crafts workers for higher productivity and quality of
work in construction projects. Our local contractors have not been using
incentives for motivation, unlike the multinational construction firms.
iv. The study will add to the body of knowledge on the factors that can really
affect productivity and quality of work in Nigerian construction industry.
v. It will encourage building and civil engineering scholars to research further
into other factors that tend to limit or affect the productivity of craftsmen.
vi. Finally the study will provide probable solutions to the worrisome problems
of poor quality of work and low output pledging our local construction firms.
1.7 Scopes and Delimitation
As highlighted in the statement of problem, the influencing factors on quality of
work and productivity of craft workers in our indigenous construction companies
are quite many and more than what can be investigated in this study. However, the
study will focus on the problems of inadequate workforce planning and control of
6
craftsmen, non-use of motivational incentives on craftsmen and inadequate
education and training of craftsmen for higher productivity. The geographical
scope of the study is the entire six geo–political zones of Nigeria.
7
CHAPTER TWO: LITERATURE REVIEW
2.1 Trade Classification of Construction Craft workers
NIOB-NBCS (2005) defined a craftsman as one who has acquired the skill in one
or two trades and certified by a master craftsman after a period of supervised
training and has the potential to work on a construction project. The institute
further classified construction craftsmen into three groups namely; structural
craftsmen comprising carpenters, masons, steel fixers, and metal fabricators;
finishing craftsmen comprising plasterers, tillers, glazers, painters and decorators;
services craftsmen are plumbers and electricians. Chitkara (2006) in his
classification of construction workers listed tradesmen as fitters, welders, sheet
fabricators, auto-electricians, auto-mechanics, and air condition mechanics.
2.2 Craftsmen Job and Work Standard:
2.2.1 The job of craftsmen
Historically, since the erection of the first house and bridge on earth, craftsmen
have been the life wire of construction work and provision of houses and
infrastructure for human habitation, transportation and other economic uses.
According to NIOB-NBCS (2005), craftsmen are people who directly apply their
human skill and ingenuity on construction work that all together produce complete
building structure of different designs and types, roads and bridge structures. By
training, craftsmen have acquired hand-on-tool vocation, physical vigor and
resilience to perform the practical construction work such as concreting, block and
bricklaying, carpentry work, metal welding and fabrication, steel erection,
painting, decoration, plumbing, auto-mechanics and maintenance etc.
8
2.2.2 Work Standards for Craftsmen
Craftsmen productivity standard or norm refers to already recorded productivity
data indicating the extent of effort required in terms of man-hours to accomplish a
unit quantity of specified work or activity. The standard express the direct effort of
craft workers and do not include the indirect effort of supporting staff on site.
According to Adrian (1982), planners and estimators can obtain productivity data
by analyzing workers performance on the previous construction work, or by
carrying out work-study research on their crafts workers. As a fast measure they
can obtain productivity norms from those published by professional institutes and
building research centers. The standards are therefore used to estimate the amount
of labour required for each work activity in the project. An example of workers
output standards is shown in table 2.1.
Table 2.1 A Typical Workers Output Standard, (Chitkara. 2006)
SI. Gang Size Out put per day (8 Hrs) No. Activities Units Skilled Unskilled
1. Excavation in ordinary soil (manually) CM - 2 7.00 2. Backfilling with excavate earth (manually) CM - 3 15.00 3. Concrete mixing and pouring in place CM 2 10 17.50 4. Making, fixing & removing of fair face formwork SM 2 1 10.00 5. Making, fixing & removing of ordinary formwork SM 2 1 11.50 6 Reinforcement making & fixing MT 2 1 0.30 7. B.R.C. fabric cutting & fixing SM 2 1 165.00 8. Bitumen paints (2 Coats) SM - 2 40.00 9. Blockwork & plaster (including scaffolding upto 4) (i) Solid blockwork SM 2 2 15.00 (ii) Hollow blockwork SM 2 2 17.00 (iii) Fairface blockwork SM 2 2 12.00 (iv) Internal plaster (single coat) SM 2 2 30.00 (v) Internal plaster (double coat) SM 2 2 20.00 (vi) External plaster (single coat) SM 2 2 20.00 (vii) External plaster SM 2 2 15.00 (viii) Screed in flooring (upto 75 mm thick) SM 2 2 20.00 (ix) Erection of scaffolding (above 4m upto 15 m nt) SM - 2 35.00 (x) Dismantling of scaffolding SM - 2 100.00 10. Tiling work (A) Ceramic wall tiles SM 1 1 6.00 (B) Ceramic floor tiles with cement back SM 1 1 7.50
9
Table 2.1: Contd,
(C) Ceramic tiles with adhesive backing SM 1 1 7.50 (D) Mosaic the work SM 1 1 9.00 (E) Mosaic skirting RM 1 1 27.00 (F) P.V.C tiles work with adhesive SM 1 1 45.00 (G) P.V.C. skirting with adhesive SM 1 1 60.00 (H) P.V.C steps No. 1 1 5.00 (I) Mosaic steps making No. 1 1 5.00 (J) Mosaic steps fixing No. 1 1 6.00 11. Situ flooring SM 1 1 2.50 Situ skirting RM 1 1 8.75 Situ steps RM 1 1 1.50 12. Threshold fixing No. 1 1 12.00 13. Sanitary accessory fixing No. 1 1 10.00 (including cutting of fixed tile if necessary) SM 1 1 10.00 14. Marble work-Floor 15. Painting: (i) 2 Coast of Snowcem SM 1 - 24.00 (ii) 3 Coast of emulsion SM 1 - 12.00 (iii) 4 Coats of enamel paint SM 1 - 10.00
2.3 Workforce Planning and Supervision of Construction Workers :
2.3.1 Workforce Planning Procedure
Bennett (1985) posits that project work planning is primarily focused on
determining the size of workforce, structuring workforce into functional groups
and team and scheduling the entire workforce to match requirement. Chitkara
(2006) also described workforce planning as chiefly identifying the trades and
skills required in a project, establishing and applying productivity standards that
will determine the number of workers needed to perform a given task in a specified
time, scheduling and organizing work force into operation team. The responsibility
for workforce or manpower planning falls in the arms of the Planning Engineer,
the Construction Manager or the Planning Department and each of them may take
the following steps.
10
2.3.2 Trades and Skill Identification
Construction involves multi-skill technology for its wide range of related activities.
These skills vary with the nature of job, type of project and corporate policy of the
construction firm. According to Chitkara (2006) the first step in manpower
planning is to identify required trades and skills using the contract documents,
comprising the drawings, specifications and the bill of quantities.
2.3.3 Estimation of Workers Output
Craftsmen output in construction projects are estimated in two ways. First, in terms
of total man-hour input in construction work; an established output standard of
craftsmen on various trades will indicate an average time a craftsman working with
a gang of unskilled labour will spend to produce a certain amount of work. Such
output standard, are usually obtained as indicated in table 2.1. They will be used by
the estimator to determine the total hour input contribution of craftsmen in a
construction project. Secondly, using the same output standard, the estimator will
be able to calculate total cost contribution of craftsmen in a project. A typical man-
hour output and cost contribution of craftsmen in a construction project is shown in
Table 2.2 below. Both contributions are regularly used in work programming and
cash flow management.
11
Table 2.2: A Typical Man-Hour Output and Cost Contribution of Craft Workers in a
Construction Project. [Source: Chitkara, 2006]
Duration Direct labour crew B.O.Q Work centre
No Activity Unity Quantity Hours Skilled Unskilled Code Responsible 1 Layout for excavation - - 4 - 2 A1-1 Earthwork 2 Excavation with machine CM 400 8 1 “ “
3 Base preparation SM 360 16 4 10 “ “
4 Anti- termite at base SM 362 4 - 2 A1-4 “
5 Polythene sheeting SM 362 6 - 3 A1-6 “
6 Shuttering for blinding RM 90 8 2 2 A1-7 “
7 Placing concrete M-100 CM 18 18 4 5 A1-6 Concreting
8 Layout for raft - - 4 1 2 A1-8 Rebar
9 Shuttering for raft SM 22.5 8 2 2 “ “
10 Reinforcement for raft MT 6.066 32 10 5 A1-11 “
11 Raft concreting M-250 CM 88.14 5 5 6 A1-8 Concreting
12 Curing raft - - - - 1 “ Backfilling
13 Bitumen coating raft sides SM 362 3 2 3 A1-5 “
14 Layout for plinth wall - - 4 - 2 A1-8 Shuttering
15 Wall shuttering SM 485 48 8 10 “ “
16 Wall concreting M-250 CM 43.78 5 6 “ Concreting
17 Deshuttering - - 16 8 8 “ Shuttering
18 Curing wall - - 8 - 1 “ Backfilling
19 Bitumen coating wall and raft SM 319 3 2 3 A1-5 “
20 Backfilling CM 120 8 - 4 A1-2 “
21 Plinth filling CM 305 16 - 8 A1-3 “
22 Anti- termite under GF slab SM 172 2 - 2 A1-4 “
23 Polythene sheeting SM 225 3 - 2 A1-6 “
24 Shuttering for GF slab SM 11 8 1 1 A1-9 Rebar
25 Weld mesh fixing MT 0.651 8 4 2 A1-10
26 GF concreting M- 250 CM 28.34 2 5 6 A1-9 Concreting
27 Curing GF slab - - 8 - 1 ” Backfilling
Total man-hour 1202 1304
All-in rate per man-hour $ 1.50 $ 1.25
Direct Labour Cost $ 1803 $ 1630
12
2.3.4 Construction Methodology
This aspect of planning is critical to the entire work planning. Ayo (2004) posit
that construction methodology is a professionally throughout synthesis of the
construction project activities with the objective to minimize cost and optimize the
use of resources to give a suitable level of production flow. Construction
methodology is a statement of the engineer’s idea of how the construction process
of a building or road project would best be executed. This is normally documented
as method statement for the consultant’s approval before actual construction at site.
The engineer will study each key operation in a project and decide on the most
optimum method of carrying out the operations. He will base his decision on
available designs and contract conditions. For example some operations may
require total mechanization while others may require only manual method or both.
In preparing the method statement, the engineer will consider the following
guidelines
a) Technical personnel available for the project and their experiences
b) Tools, plant and equipment that could be made available for the project either
directly owned or to be hired.
c) Technology that is available in the industry
d) Contract conditions in terms of period, access etc.
e) Site conditions and constraints.
2.3.5 Critical Path Method network Analysis
CPM is one of the three network methods of analyzing and determining the
duration of construction work. It is up to the engineer to choose the method that
will be suitable for his project: CPM network is drawn after the construction
13
methodology has been finalized. It is the task of an experience engineer to develop
the CPM network .An example of a CPM of a road project is show in figure. 2.1.
14
Fig 2.1 Dual road construction critical path network
E
10
12 3 12
F
10
22 4 22
J
6
32 6 32
8 L
38 9 38
A
4
0 0 0
C
8
4 1 4
D
10
12 2 12
G
12
20 5 22
I
12
32 8 34
L
2
46 10 46
48 1 48
H
12
20 7 22
B
4 EST LST
EST = Earliest Start Time
LST = Latest Start Time
Critical Path Events =
15
2.3.6 Work Programme
Work programme according to Bamisile (2004) is a construction project schedule
set data-wise in a logical sequence; it is a timetable for action. It implies
programming of the chosen work plan on a calendar basis and provides the base
against which all progress is measured. The method of presenting work programme
varies depending on the planning technique used and the nature of task to be
performed. Most construction projects are programmed using bar chart method
whereby works are first split into activities and then listed in the order of
construction priority on the left side column, while the time scale is plotted
horizontally on the top and or bottom of the chart. When the work programme is
properly drawn out by an experienced engineer, it will be used to schedule
workforce requirement in various section of the project. A typical work
programme is shown in table. 2.2.
16
Table 2.2 Work Programme for the construction of 2nd
6km length + 4 culverts dual road
ACTIVITY
D U R A T I O N
Jan Feb Mar April May June July Aug Sept Oct Nov Dec Site Clearing
Removal of Trees
General excavation
Grading Culvert 1 & 2 Culvert 3 & 4
Earthwork Drainage Pavement Kerbs
Walkway Clean up
17
2.3.7 Scheduling Construction Workforce
Walker (1984) stated that construction workers on project sites are employed to
perform specific tasks. These workers include supervisors, craftsmen, labourers,
operators, mechanics, drivers etc, and for ease of estimating, planning, accounting
and controlling the workers, they are broadly divided into two categories; the direct
or construction workers and indirect site workers or support manpower. According
to Austen (1984) direct construction workers are those that can be identified with
the execution of an activity of permanent works as listed in the BOQ. They include
foremen, tradesmen and trade helpers. Anderson and Woodhead (1981) clearly
posit that project manpower scheduling must be carried out using the bar chart
programming of construction work. The work programme chart indicates the date
of commencement and completion of each activity of work item, and work content
as contained in the BOQ. The daily average manpower required for each scheduled
activity can be assessed as follows:
MPW required = quantity of work x Labour Productivity standard in man-days ÷
Duration in days
The ratio of the skilled and unskilled labour in construction gang depends on the
characteristics and nature of work. The aggregation of manpower required for the
scheduled activities on the chart indicates the daily strength of workforce,
category-wise required to accomplish the scheduled work according to the project
plan.
Daily workforce required for scheduled work = sum of construction manpower for
the scheduled activity on data.
An example of monthly workforce scheduling is shown in table 2.3
18
Month Shuttering
carpenter
Mason
Conc.
Mason
finishes
Steel fixer Plumber Electrician Operators Trade
helper
Gen.
helper
Total % Cum%
1 18 2 0 10 4 2 2 17 7 62 0.51% 0.51%
2 33 15 0 17 6 5 4 25 32 137 1.14% 1.65%
3 47 13 0 27 6 7 11 37 59 207 1.72% 3.37%
4 48 21 0 32 6 8 12 39 82 248 2.06% 5.42%
5 63 26 8 32 6 8 14 58 105 320 2.65% 8.07%
6 63 26 21 24 6 9 21 95 120 385 3.19% 11.27%
7 98 26 27 35 9 9 24 84 195 507 4.02% 15.47%
8 115 28 30 40 9 9 35 156 162 584 4.84% 20.31%
9 121 31 48 41 12 10 39 173 192 667 5.53% 25.84%
10 156 24 55 50 13 10 39 196 199 742 6.15% 31.99%
11 193 30 62 54 14 13 43 247 170 826 6.85% 38.84%
12 199 33 68 55 14 18 47 278 283 995 8.25% 47.09%
13 202 23 83 61 16 19 50 277 288 1019 8.45% 55.53%
14 202 23 83 61 16 19 50 300 265 1019 8.25% 63.98%
15 197 23 83 60 19 22 46 302 263 1015 8.41% 72.39%
16 186 0 83 60 20 22 47 280 268 966 8.01% 80.40%
17 153 0 83 60 20 22 46 280 286 950 7.88% 88.28%
18 104 0 83 47 20 22 38 212 258 784 6.50% 94.78%
19 72 0 70 27 20 22 29 143 247 630 5.22% 100.00%
Total 2270 244 887 793 236 256 597 3199 3481 12063 100.0%
Table 2.3: A monthly workforce schedule for typical building project
19
2.3.8 Work Grouping of Workforce
In a typical site, workforce is grouped according to work breakdown or activities.
Each work breakdown is assigned a team leader who may be an engineer, a
builder, a foremen or supervisor, leading technical and tradesmen to work in a job
section. With the work grouping, every craftsman is traceable to a task force or
gang. A taskforce will operate without much interference from the other groups.
Fig. 2.2 A typical work grouping chart (section)
The manpower strength of every work task depends on the nature and size of the
task. It usually ranges from 10 to 30 workforces.
2.3.9 Supervision process
Effective site supervision must follow a laid down process which, sometimes will
be according to a company’s policy. Work supervision is the sole job of the
engineer or the construction manager and his assistants, the supervisors or
foremen. Every section of construction work must have adequate number of
craftsmen, artisans and labourers at work. This group of workers, usually in large
Head Carpenter Carpenter
Head Mason Masons
Head Fitter Fitters
Head Labour Labours
Construction Manager (Substructure)
Supervisor/Foreman
20
number, especially in complex building projects must be properly supervised to
ensure that they carry out their various jobs according to production drawings and
specification. The engineer and the supervisors are expected to use the following
criteria for effective work supervision;
i) Engage tested and proven artisans, craftsmen, suppliers, and subcontractors
in all aspect of site production operations.
ii) Strictly follow all the construction methodology.
iii) Ensure that works are carried out in accordance with the construction
programme.
iv) Use appropriate instruction sheet to direct and control how each operation is
to be carried out on site.
v) Use check list for the continuous inspection of each operation as it is being
carried out. It is the duty of the engineer to prepare the instruction sheets
and the check lists. Samples of instruction sheets and checklists are
shown in tables 2 4, 2.5, 2.6, 2.7 and 2.8 below
21
Table 2.4 Work Instruction Form (Bamisile 2004)
ABC LIMITED: WORK INSTRUCTION
PROJECT…………………………………. GRIDLINE/REF…………………….
STAGE OF WORK…………………………. TRADE/ELEMENT………………….
CHECKLIST REF…………………..
DESCRIPTION OF WORK OPERATIONAL METHOD
MATERIALS REQUIRED
LABOUR REQUIRED
PLANT/EQUIPMENT
Operation Start Date………………………..
Prepared
By………………….Date………….
Duration of Operation……………………….
Approved by…………………Date…………
22
Table2.5 Setting out Checklist (Bamisile 2004)
ABC LIMITED: SETTING OUT CHECKLIST
PROJECT……………………………………………………………………….
LOCATION/BLOCK NO………………………………………………………
S/N WORK ITEMS CHECK DATE REMARK& SIGN
1
2
3 4
5 6 7 8
Confirm site dimension
Set Backs-Front -Back
-Right side -Left side
Profile lines Measurements- Length
-Width -Diagonal -Recesses
-Projections
Squarness General Arrangements
Angles Curves (If necessary)
General comments………………………………………………………………………………
…………………………………………………………………………………………………. …
Setting out Approved (name)……………………….. Sign ………………. Date…….
23
Table 2.6 Strip Foundation Checklist (Bamisile 2004)
ABC LIMITED: STRIP FOUNDATION CHECKLIST
PROJECT…………………………………………………………
LOCATION/BLOCK NO…………………………………………..
S/N WORK ITEMS CHECK DATE REMARK& SIGN
1.0
1.1
1.2
1.3
1.4
1.5
1.6
1.7
2,0
2.1
2.2
2.3
2.4
2.5
3.0
3.1
3.2
3.3
3.4
3.5
4.0
4.1
EXCAVATION
Width of excavation
Depth of excavation
Suitability of formation level
No soft spot SE&QS Informed of Variation Blinding Depth of concrete footing REINFORCEMENT (IF ANY)
Type of bar
Bat sizes
Bar centres
Cover (top, side,& bottom)
Starter bar position & level
CONCRETING
Pockets Pocket (box outs) Mixing Placement & compaction Finished level Cube taken & late date recorded POST POUR Curing
General comments…………………………………………………………………………
……………………………………………………………………………………………….
Foundation Approved by (name)………………… . .Sign………………….. Date…………
24
Table 2.7 Piling Checklist (Bamisile 2004)
ABC LIMITED PILING CHECKLIST
PROJECT…………………………………………………………
LOCATION/BLOCK NO………………………………GRIDLINE………………………….
S/N WORK ITEMS CHECK DATE REMARK& SIGN
1
2 3
4
5
6
7
8 9 10
11
Test Piling Installation of inclinometer (if necessary) Diameter of bore
Depth of drilling
Reference to datum
Lining
Reinforcement
Concrete mix
-Placement & compaction -Sample of cube test
-slump measured Pile cap formation levels Pile test
Recorded pile test results
General comments………………………………………………………………………………
…………………………………………………………………………………………………..
…………………………………………………………………………………………………….
Piling Approved by(name)……………………………Sign ……………….Date……………
25
Table 2.8 Piling Cap Checklist (Bamisile 2004)
ABC LIMITED PILING CAP CHECKLIST
PROJECT…………………………………………………………
LOCATION/BLOCK NO………………………………GRIDLINE………………………….
S/N WORK ITEMS CHECK DATE REMARK& SIGN
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
Excavation level correct
Formation n level suitable
Excavation size correct
Consultant SE& QS informed of
variation to drawing (if any)
Position and orientation correct
Blinding level correct
Reinforcement -bar sizes
-centres -cover
–starter bars M&E sleeves
Formwork
Concrete mix record of delivery ticket.
Cube taken/date recorded
Slump measured
Concrete placement & compaction
Finish to top of pile cap and ground
beam correct
Curing
General comments……………………………………………………………………………
……………………………………………………………………………………………….
Pile cap/Ground beam Approved by (name)……………… Sign ……………Date…….
26
2.4 Productivity Control of Workforce :
2.4.1 The Control Concept
Alfred (1988) gave the view that labour productivity control achieved on a project
site will provide a measure of the labour efficiency, show the total time for which
the labour was employed at work, the time he was productive on work and the time
he remained unproductive. Chitkara (2006) reported that studies carried out on a
construction site revealed that the workers productive work time varies from 50 to
70% of his total employment time and the remaining time is wasted for various
reasons such as idle waiting, unnecessary movement, late starting, early quitting,
unscheduled break, delay in the receipt of tools, materials and work instructions.
Anderson and Woodhead (1981) suggested that the labour control process would
include accounting of actual productivity time, comparing the actual time with the
standard, analyzing the causes of any variance between the actual and standard and
finally taking remedial measures to improve productivity.
2.4.2 Establishing Labour Accounting System
Chitkara (2006) recommended that labour accounting system should be designed
to serve many purposes; to enable computation of accurate payment of
construction workers, to provide data for the evaluation of labour productivity for
various tasks and facilitating the estimation of labour costs of work executed. He
further stated that the same labour accounting system provides the information and
record keeping requirement of the entire project department, especially those of
personnel, accounting, costing and planning. Chitkara, gave his model of labour
accounting system as shown below:
27
Fig. 2.3 Labour Accounting System. (Source: Chitkara, 2006).
Productivity accounting is the time-keepers’ daily time records for the labourers
and craftsmen, foremen daily employment records
2.4.3 Time-Keepers’ Daily Recording
Chitkara maintained that the first step in productivity evaluation is to record
payable time. The timekeeper keeps the labour time account and the basic
document used for this purpose is the time card. The time-card record the daily
attendance time of the worker, details of his trade time in and time out, and
possibly the task he is employed. The workers’ time cards are submitted to the
personnel department by the timekeeper, at specified interval for pay rolls and
wage calculation. A specimen of a time card is shown in table 2.4. Time-card data
ensures that a worker is paid exactly what is due to him.
Administration Center
Time Card Development Centre
Productivity
Manpower Forecast
Cost Analysis
Pay-roll
Labour Cost Forecast
28
Table 2.9: A typical Labour Time Card for Craftsmen (Source: Chitkara, 2006).
2.4.4 Foreman’s Daily Labour Employment Report
Also according to Chitkara, a typical foreman’s daily labour report is based on the
time-keeper record and will include the work activity for which a worker or crew
member was employed on productive work and his idle time breakdown with
causes. The report will indicate the quantity of work done on a daily basis by the
worker. The foreman’s daily labour employment statement, at the end of each day
is forwarded by him through his construction manager/project engineer to the
productivity monitor. A specimen of foreman’s daily labour report is shown in
table2.10
No Category Name
Work Centre/Dept./Work Package Cost Code
Normal Working Time Over Time
DATE IN OUT IN OUT Hours Hours
Total
For use by Accountant
Normal wages Overtime wages Total
Deductions
Amount payable
29
Table 2.10 Foreman’s Daily Labour Report (Source: Chitkara, 2006).
S1
No
Workers’
Names/code
Daily
Grand
Total
(Hrs)
Dated:
Non-Productive Man-Hours
Act
A
Act
B
Act
C
Work
P
Item
Work
Q
Item
Total
(Hrs)
Sick
Def
work
Waiting for
Work
Instruc
tion
Epuip
ment
Mat-
erials
Bad
Weather
Interrup
-tion
Other
duty
Total
Current total
Previous
Employment
Total
employment
Work
Done
Qty
Unit
Productivity
Work/MH(O
QW)
30
2.4.5 Construction Manager Weekly Labour Productivity Report
Like the Foreman’s report and the Timekeeper’s daily report, the construction manager
weekly labour productivity report is based on the foremen’s daily report, after thorough
scrutiny. The manager’s report is done collectively on each time of the work and used
to monitor labour performance and evaluate labour cost for each item of work. The
report provides a device to compare the operating efficiencies of different task force
and helps to forecast the labour workforce required for the remaining similar work. The
manager labour report becomes the bases for developing labour productivity norms for
use in future similar works. See table 2.11 below.
Table 2.11 Construction manager weekly labour productivity reports Chart. [ Chitkara 2006)]
2.5 Productivity Motivation of Construction Workers :
2.5.1 Motivational Objectives
Chitkara (2006) opined that the art of motivating lies in creating the environment,
developing systems and directing efforts in such a way that they meet the
organizational goals as well as the needs of those participating in the process, with
everyone working enthusiastically as one team under the leadership of the
construction manager. The motivational approach, in general can be divided into
Date Crew Milk Actual MH
on date
Actual MH
Cumulative
Quantity work Productivity
actual
Productivity
standard
Skilled Unskilled Complete Cumulative
31
behavioural approach and financial incentive schemes. In a construction project the
behaviour motivational approach is to create a healthy work environment while the
financial incentive scheme benefits the participant in the following ways,
� It assists management is increasing production and productivity without any
appreciable increases in cost, by curtailing supervision time, obtaining
reliable feedback in progress of work and productivity, and increasing
effective control on the employment of workers.
� It helps workers in increasing their earnings and gaining job satisfaction
without affecting the estimated costs of work. It also encourages workers to
develop better method of working.
In all, and in view of the benefits, the management of construction firms should
ensure that such policies, which motivate workers, are put in place for every
project site.
2.5.2 Types of financial incentives
MacCaffer & Harris (2001) argued that financial incentives are those intended to
remove sub-standard performance and encourage increase in output by payment of
bonus money relative to the level of production. Workman understand financial
reward than any other and can achieve and maintain a pace of work up to 331/3
percent above his normal, without loss of quality or personal strain. This incentive
scheme is specifically meant to encourage productivity, good quality of work and
operatives more earnings without increasing unit cost. Examples of financial
incentive schemes are:
i. Profit Sharing: bonus that a company pays out either yearly or half yearly in
lump sum or shares to its employees based on the profit earned by the
company.
32
ii. Day work payment: where an hourly rate is paid relative to the skill required
by the task, the worker is then simply paid for performing on the work. This
system is most suitable for craft operatives where there is great complexity
involved or a high level of skill is required.
iii. Piecework payment: this is the payment of a uniform price per unit of
production, as the worker improves output, earnings increases
proportionately.
2.6 Effective Communication on Construction Site :
2.6.1 What to communicate on site
A construction site is like a factory that is organized to produce a building structure
or road infrastructure. As a factory, various classes of people are involved in
production and everybody has to comprehend direct instructions and carry out
expected duties. According to Nwosu (2007) in a construction site there are many
issues and instructions to be communicated within the site and from the head
office, for the smooth running of the project. Every activity on site requires
effective communication to enhance better result. Issues to be communicated on a
project site include;
� Policies, goals and objectives of the company regarding the project
� Construction drawings, specifications and schedules
� Construction safety, health and welfare instructions
� Site progress reports and possible changes
� Additional works, variations, materials and plant movement
� Consultants inspection visits, instructions and meetings
� Periods of payments to workers, subcontractors and suppliers
� Bonus and incentive packages
� Requirements, transfers, sack or death of any worker
33
� Purchases and delivery of materials etc
2.6.2 Channels of communication on site
Johnston (1981) argued that communication is a vital part of any organization and
no less so than in the construction sites where activities are scattered, decisions and
instructions often needed urgently. Work often goes wrong on site because of poor
communication, particularly among those responsible for implementing
instructions. The accepted medium for giving instructions and receiving
information on site is by verbal, written or telephone transmissions but these
mediums are rarely coordinated correctly with the result that information
occasionally conflicts. A survey of construction sites reveals that project
communication flows in a family tree pattern. A formal line of communication on
a typical construction project is shown in fig 2.5 below.
Whatever that needs to be communicated could be done properly and faster to the
least person using the organization chart.
Fig. 2.4: Site Communication chart
SCM = Senior Construction Manager CM = Construction Manager
SCM
CM
Substructures
CM
Substructures
CM
Finishing
CM
Ext. Wks
Supervisor Supervisor Supervisor Supervisor
Head
Mason
Head
Carpenter
Head
Fitters
Head
Labourer
34
2.7.0 Quality Control of Construction Work:
2.7.1 Quality Control Objectives
Calvert (2000) opined that maintenance of quality is an important factor in modern
construction and on large work it may justify the full time employment of special
personnel and expensive laboratory facilities. Harris and MacCaffer (2001) on the
other hand, stated that as quality means meeting the requirement of the customer,
control refers to the intention to ensure that the quality is achieved. Both authors
emphasized that the major objectives of quality control can be listed as follows:
� To ensure that completed work meet the specifications
� To reduce customers’ or client’s complaints
� To improve the reliability of products or work produced
� To increase customers’ confidence
� To reduce production cost.
2.7.2 Quality Control Criteria
Quality control is primarily concerned with defect detection and the central feature
of all quality control is that of inspection. To be effective the construction process
requires that work items to be inspected must be catalogued into a quality
schedule, Harris and MacCaffer (2001).
During construction, inspection takes two forms; the quantifiable or measurable,
e.g. lines, levels, verticality and dimensions and visual checks which is subject to
the inspector’s interpretation; e.g. fitness, tolerance and cleanliness. Also,
according to Harris and MacCaffer, two sets of documents are used to facilitate
quality control drawings and specifications. The quantifiable quality checks
include ensuring accurate setting-out and leveling, testing the strength of concrete
cubes, checking alignment of brickwork and commissioning of services
35
installations. Visual quality checks of each section of construction are undertaken
by the contractor’s engineers, and foremen and then by resident representation of
the consultants to ensure compliance with the drawings and specification. The
result of quality checks are recorded and passed on to the resident engineer or
builder. It is however of a necessity that the contractor’s engineers and operatives
should have a clear knowledge and understanding of the quality required and also
able to achieve it first time or regulate it by inspection. This will immensely reduce
the risk of producing unsatisfactory work and being involved in expensive re-work.
2.7.3 Quality Control of Road Projects
Kadyali & Nal (2008) stated that quality control of road construction work will
normally proceed from the quality assurance system on a project adopted by the
client or by the project manager/consultants. The contractor will receive this piece
of document as part of the contract conditions which he would have accented to
during contract award.
On a typical road project, a contractor is required to adopt different stages of
quality control measure.
Preliminary Control Tests
Before any work on the construction of a road pavement is commenced, it is
necessary to conduct certain preliminary test on soils and other pavement materials
incorporated in the design to check if these materials meet the specified quality
requirement such preliminary tests should be conducted of the following materials.
a) Borrow material: After identifying a potential borrow area griddled at 25m centres to full
depth of proposed work, the test pits should be logged and plotted for proper identification
of suitable sources of materials. Any of the following tests can be done on representative
soil samples,
-sand content,
-plasticity index,
36
-density test, or deleterious content,
-moisture content,
-CBR test on the material to be incorporated in the subgrade on soaked/unsoaked sample.
b) For checking suitability of non-bituminous base/subbase materials
-Natural moisture content
- Grading
-Liquid limit and plasticity index
-Specific gravity
-Water absorption
-Durability of aggregates (soundness test)
-LA Abrasion value/aggregate impact value text
c) For proportioning Soil-Aggregate/Stabilized Soil Mixtures
-CBR tests
-Compaction tests (Mod AASHTO for MDD and OMC)
-Unconfined compressive strength (for lime/cement soil mixes)
d) For Bituminous Materials in Base/Binder/Surface Courses
-Coarse and Fine Aggregates
-Grading
-Water Absorption
-LA Abrasion value/aggregate impact value
-Durability (soundness test)
-Amount of detrimental substances
e) Mineral Filler
-Grading
-Water content
-Plasticity index
-Property change after heating
f) Bitumen
-Physical tests
(Penetration, softening point, viscosity, fire/flash points, ductility, TFOT, RTFOT etc.)
g) For Bituminous Mix Design Tests
-Marshall stability
37
-Flow
-Water sensitivity/Retention of stability etc.
h) For Cement Concrete
-Cement: Physical and chemical tests
-Aggregates:
-Gradation
-LA abrasion/aggregate impact value
-Soundness
-Alkali aggregate reaction
-Workability
-Concrete strength
Preliminary inspection of Performance of Equipment
All types and pieces of equipment/plant to be used in the project should be subjected to
preliminary inspection before use. For example, a hot bituminous mix plant should be checked
for its capacity, type/method of supplying aggregate, dryer capacity, dust collector type, mixer
type and capacity, weighting system etc.
Trial Construction
For medium to large projects, trial mixes are produced to check the rate of production (per hour);
proportions of aggregates; amount of bitumen; mixing time; heating, mixing and discharge
temperatures etc. For major large-sized projects, trial paving may be undertaken on full scale
with a view to confirming the work procedure proposed to be adopted, confirming mixture
properties, establishing acceptance, rejection criteria, thickness of spreading and compaction
conditions etc.
Controlling Workmanship during Construction
The formation of the pavement should be controlled on the basis of the height of finished surface
of the sub-base (or base, if no sub-base is to be provided), the proposed height being
measured every 20m length. The pavement width should be controlled on the
finished sub-grade surface. For the control of thickness of each layer, the thickness is calculated
as the difference between the measured heights of the upper and lower surfaces of the layer,
except that the thickness of the surfacing, binder course and bitumen treated base
course should preferably be determined with sampled cores.
38
The standards for controlling workmanship would obviously depend on the
inspection standards, size of the project, professional level of site personnel etc.
The recommended tolerance and frequency of measurement for workmanship are
as given in Table 2.12 below;
Table 2.12 Frequency of Inspection and Tolerances in Workmanship (Kadyali & Nal, 2008)
Pavement Course Measurement Frequency of inspection Tolerance
Subbase Height of finished subbase Thickness Width
Every 20 m Every 20 m Every 20 m
± 40 mm -45 mm -50 mm
Mechanically Stabilised base Thickness Width Every 20 mm Every 100 m
-25 mm -50 mm
Asphalt treated base Thickness Width Every 1000 m2
Every 100 m -15 mm -50 mm
Cement or lime stabilised base Thickness Width Every 20 m Every 100 m
-25 mm -50 mm
Binder and surface Hot asphalt mixture
Thickness: Surface Thickness: Binder Width Evenness
Every 1000 m3 Every 1000 m3 Every 100 m Throughout the length in every lane
-7 mm -9 mm -25 mm 2.4 mm* or less
Controlling Quality during Construction
Quality control during road construction is necessary to ensure that the pavement is
so constructed as to meet the various requirements of specifications and design
documents. Such a quality control involves a variety of tests to be conducted
during construction with regular frequency and obtaining all the relevant
construction data for statistically processing the test results. The different types of
tests to be conducted and their frequency for earthwork, granular subbases and
base courses, pavement layers involving bituminous and cement concrete
construction work are given in Table 2.13 below;
Table 2.13 Frequency of tests for quality control (Kadyali & Nal, 2008)
S/NO. Item of work Frequency
1. Earthwork (i) Soil particle size, Atterberg Limits (ii) C.B.R. on a set of 3 specimens
1-2 tests per 8000m3 One test per 3000m3
39
(iii) Natural moisture content (iv) Moisture content before compaction (v) Dry density of compacted area
One test per 250m3 2-3 tests per 250m3 One test per 1000m3 for embankments to be increased to one test per 500-1000m3 fro subgrade layers.
2. Gravel sub-base (i) Gradation, plasticity (ii) Moisture content (iii) Density
One test per 200m3 One test per 250m2 One test per 500m2
3. Lime-soil (i) Purity of lime (ii) Lime content, moisture content (iii) Density
One test per 5 T One test per 250m2 One test per 500m2
4. Water-bound macadam (i) Los Angeles Abrasion or Aggregate Impact Value, Flakiness Index (ii) Grading of materials (iii) Plasticity of binder
One test per 200m3 One test per 100m3 One test per 25m3
5. Bituminous Macadam (i) Los Angeles Abrasion Value or Aggregate Impact Value, Flakiness Index, Stripping Value (ii) Mix grading, binder content, aggregate gradation
One test per 50 – 100m3 One tests per day
6. Surface dressing and premix carpet (i) Los Angeles Abrasion Value or Aggregate Impact Value, Stripping Value, Flakiness Index Water absorption (ii) Grading of aggregate (iii) Rate of spread of binder and aggregate for surface dressing (iv) Binder content for premix carpet
One test per 50m3 One test per 25m3 One test per 500m2 Two tests per day
7. Asphaltic concrete (i) Los Angeles Abrasion Value or Aggregate Impact value, Stripping Value, Water absorption, Flakiness Index (ii) Sieve analysis for filler (iii) Mix grading, binder content (iv) Stability (v) Thickness and density
One test per 50 – 100m3 One test per 5m3 One test per 100T of mix, minimum 2 tests per day. 3 Marshall specimens per 100 T of mix. One test per 500m2
8. Cement concrete pavement (i) Gradation of aggregates (ii) Los Angeles Abrasion Value or Aggregate Impact value, Soundness (iii) Cement, physical and chemical (iv) Workability (v) Concrete strength (vi) Core strength on hardened concrete
One test for 15m3 Once for each source Once for each source One test per 10m3 3 cube/beam samples for each 7 days and 28 days for every 30m3 of concrete 2 cores for every 30m3 of concrete.
2.7.4 Statistical Methods in Quality Control of Highway Construction
Normal distribution method
It is generally found that the properties of highway materials and end product, when tested a
number of times with samples from the same lot or the same work, follow a “normal
40
distribution”. The normal density function, also called the Gaussian function, is given by the
following equation:
2
2
1
2
1)(
−−
= σ
µ
πσ
x
exf equ. 2.1
For - ∞ < x < + ∞. A typical shape of this function is given Fig. 2.6.
Fig. 2.5: Normal distribution curve.
It is seen that the curve is bell shaped and is symmetrical with respect to µ , the population mean.
A useful transformation of this equation is obtained when µ = 0 and = 1. The variable z, known
as the standard normal variable, is defined as:
σ
µ−=
xz equ. 2.2
Equation (2.1) then becomes
2/2
2
1)( zexf −=
π equ. 2.3
The above relationship is given in Fig. 2.6, which is known as the standard normal density curve.
Area F-(Z1) = φ (z1)
2/2
2
1)( z
ezf−=
π
x µ
f (
x)
2
2
1
2
1)(
−−
= σ
µ
πσ
x
exf
- 3 - 2 -1 0 1 z 1 23
f (
x)
z
41
Fig. 2.6: Standard normal density curve
The area below this curve is unity. Standard tables are available giving the value of the area
under any part of the normal curve for different values of z. In these tables, the cumulative unit
normal distribution, or F(z), is plotted for various values of z above 0. By symmetry, for values
less than 0, φ (-z) = 1 - Φ (z).
Mean, Standard Deviation and Coefficient of Variation method
The most common measure of central tendency of values is the arithmetic mean, or simply the
“mean”. Suppose there are n observations of a variable x (i.e., sample size = n), and these are
denoted by x1, x2, x3, ……….. xn, then the mean x is given by the formula:
n
xxxxx n++++
=....321
n
xin
i
∑== 1 equ. 2.4
When the observations are grouped into different classes, a simplified procedure enables a quick
determination of the mean A measure of the dispersion of the data is the standard deviation,
which is obtained from:
1
)(1
2
−
−
=
∑=
n
xxi
s
n
i equ. 2.5
Where s = standard deviation and xi = each individual observation
x = mean, as found from Eqn. (2.4)
n = number of observation.
It may be noted that x and s obtained from above are estimates of the true mean, µ and the true
standard deviation, σ of the population.
The coefficient of variation is defined as the ratio between the standard deviation and the mean.
42
Coefficient of variation = x
s (for the sample) equ. 2 6
= µ
σ (for the population) equ. 2.7
Distribution of Sample Mean method
When the sample mean, x is determined repeatedly with n observations, it will be found that x
also takes a normal distribution with mean µ and standard deviationn
σ. The latter is known by
the term standard error of the mean, σ x . If the value of σ is not known, σ can be taken equal to s,
the standard deviation of the sample.
Point Estimate and Interval Estimate method
The sample mean x is a point estimate of the population mean µ. It is more usual to estimate a
parameter within an interval. Thus, if t1 and t2 are two values of a random variable t and it is
desired to estimate the parameter θ, then
Pr [t1 ≤ θ ≤ t2] = γ equ. 2.8
Pr denotes the probability indicated in [ 2.8]
and γ = specified probability.
The set of values between t1 and t2 (inclusive) is called the confidence interval. The values t1 and
t2 are called the confidence limits. The probability measure γ is called the confidence level. The
confidence level is the proportion of the samples for which the interval includes the true values.
From the normal distribution table the values of the standard normal variable za, associated with
various confidence levels γ are summarized in Table 2.14. It may be noted that
2
1 γσ
+= equ. 2.9
Table 2.14: Standard normal variable associated with various confidence levels
Confidence
Level 2
1 γσ
+=
Tolerance Level (proportion of test results
that fall below the minimum)
Za
0.80 0.90 1 in 10 1.282
43
0.90 0.95 1 in 20 1.645 0.95 0.975 1 in 40 1.960
0.98 0.99 1 in 100 2.326
0.99 0.995 1 in 200 2.576 0.998 0.999 1 in 1000 3.09 0.999 0.9995 1 in 2000 3.291
Example2.1. The thickness of an asphaltic concrete layer is designed and constructed to be
80mm. the standard deviation is 15mm. What is the probability that if a sample of 100 readings
of the thickness is tested that the mean observed thickness exceeds 75 mm?
Solution µ = 80, σ = 15
σ x = 5.1100
15=
p ( x > 75) = Shaded area in Fig. 2.7
= 1
−−
5.1
8075φ
= 1 - φ (-3.33)
= 1 –[1 –φ (3.33)]
= 1 – 1 + φ (3.33)
= 0.9996, from statistical tables.
The probability that the observed mean thickness of 100 readings exceeds 75 mm is 99.96
per cent.
Example2.2. A series of 363 observations of the cube strength of concrete gives a mean of 39.7
MN/m2 and a standard deviation of 6.8 MN/m
2. Give α 95 per cent confidence interval for the
population mean.
Solution n = 363, x = 39.7, s = 6.8.
The distribution of x follows a normal distribution with mean as µ and a standard deviation of
n
σ, (known as the standard error of mean). Since σ is not known, it can be approximated by s,
the standard deviation of the sample.
.36.0363
8.6===
n
sxσ
44
For a 95 per cent confidence level, γ = 0.95. Hence the normal variable z has a value of 1.95, as
seen from Table 2.14.
With 95 per cent confidence, the population mean has a value between x + 1.96 σ x
i.e., between 39.7 + 1.96 x 0.36 and 39.7 – 1.96 x 0.36
i.e., between 40.4 and 39.0 MN/m2..
2.7.5 Quality Control on Building Projects
A large and complex building project is expected to have a Quality Control
Engineer or Manager. His duty according to Bamisile (2004), among others, is to
ensure;
i) Strict implementation of the project quality management plan and health and
safety plan.
ii) Approval for the use of each and all specific work instructions and
inspection/testing plan of the project.
iii) That the internal quality audits are carried out periodically during the execution
of the project
iv) Proper safekeeping and storage of all quality records on and off site.
Workmanship; All activities affecting quality are to be described and
accomplished with documented instructions, drawings, specifications and
checklists appropriate to the circumstances. Table 2.10 shows a typical work
instruction form.
Inspection and testing equipment: Selection of surveying, measuring and testing
equipment shall be controlled to ensure that such items are of appropriate type,
range, accuracy and tolerance for the purpose for which they are to be used. They
are to be check at intervals and by the methods shown in Table 2.15.
Table 2.15 TYPICAL INSPECTION MEASURING AND TESTING EQUIPMENT ON BUILDING SITE
[Bamisile, 2004]
45
INSTRUMENT METHOD OF TEST OR
CHECK
ALLOWABLE ERROR MAXIMUM INTERVAL
BETWEEN CHECKS
Surveyor’s level a) Two pegs
b) Circular level check
5mm in 50m
Bubble remains generally within
inner circle
On delivery and then 1 week
4 weeks or earlier if problem
suspected
Surveyor’s
precise level
a) Two pegs
b) Circular level check
1mm 30m
Bubble remains generally within inner circle
On delivery and then 1 week
4 weeks or earlier if problem
suspected
Laser level As manufacturers instructions 3mm in 50m or as manufacturers
recommend
On delivery and then 1 week
Theodolite a) Hori. Collimation
b) Vert. collimation
c) Trunnion axis
d) Rot’n of alidade
e) Optical plumet
20’’
30’’
30’’
Bubble 2 div.
3mm at 1.5m
] ] ] On delivery and then ] 4 weeks or earlier if ] problem ] suspected ] ] EDM/Total
Station
a) Hori. Collimation
b) Vert. collimation
c) Trunnion axis
d) Rot’n of alidade
e) Optical plumet
f) Dist. Measurement
against calibrated base line
20’’
30’’
30’’
Bubble 2 div.
3mm at 1.5m
Mfrs.quoted accuracy + 5mm +
] ] ] On delivery and then ] 4 weeks or earlier if ] problem ] suspected ] ]
1 week
Auto plumb a)Vertically
b) Optical plummet
30’’
3mm at 1.5m
] On delivery and then ] 4 weeks or earlier if ] problem ] suspected
Designated
- hand tapes
–steel tapes
–stylon tapes
a)Measure against
calibrated
band/ tape or base line
b)Check with calibrated
band/tape
3.5m- + 2mm
30m- + 4mm
50m- +5mm
]
] On delivery and then ] 8 weeks- stylon ] 26 weeks – steel ] or hand tapes or earlier if problem suspected
Leveling Staff a) Measured against
designated tape
+ 2mm over total length and
between section
On delivery, on sign of
damage or 6 months
Designated
spirit level
Standard check 1mm in 1m 4 weeks
Table 2.15 Contd.
46
Work inspection and test checklists: Each work section which has been identified
to require quality control, a quality inspection and test checklists, etc will be used.
The checklists are in sequential order for inspections and tests procedures to be
undertaken to verify conformity with specifications and drawings.
Non-conformity Control: All non-conformity of suppliers, to be controlled by a
laid down procedure. A parameter must be established to ensure firm control of
non-conformity. Such parameter or measures will include.
a) Identification, documentation, segregation, review or disposition of non-
conforming item of work.
b) Notification of the person or group responsible for the non-conformity.
c) Every non-conformity and concession on site should be registered and updated
by the quality engineer.
d) The quality engineer and the construction manager should carryout analysis and
assessment of non-conformity and suggest corrective action and measure to be
taken to avoid reoccurrence.
Corrective Action; Once the appropriate correction or remedy has been determined
over non-conformity the next item is to implement the correction. The senior site
manager or project manager has the responsibility to verify proper implementation.
Internal Quality Audit; Internal quality auditing of construction work is another
task of the quality control unit. This task is to verify whether qualities of the works
carried out on site comply with planned arrangement and to determine the
effectiveness of the quality control system adopted in the company.
Quality auditory is performed using checklists and will be conducted by
appropriately trained personnel not having direct responsibilities but
knowledgeable of the specific item of construction being audited.
47
The auditor at the end of his task will produce an audit report on the quality
system, which he must submit to the Executive Director. The Director is obliged to
study the report, carryout periodic analysis of the audit and most probably include
the result in the future review process on quality control. Examples of quality audit
forms are included below in tables 2.16 (a) & 2.16 (b).
48
Tables 2.16 (a) Typical Internal Quality Audit Form [ Bamisile,2004]
PROJECT AUDIT PROGRAMME 2004
Activity A F M A M J J A S O N D
Setting out x
Instrument check x
Substructure x
Insitu-concrete x
Reinforcement x
Structural steel x
Blockwork
DPM
Pre-cast concrete x
Sealants
Windows
Plasterwork
Screeding
M&E Installations
49
Tables 2.16 (b) TYPICAL INTERNAL QUALITY AUDIT FORM [Bamisile,2004]
PROJECT AUDIT PROGRAMME 2004
Activity A F M A M J J A S O N D
2.8 Education and Training of Construction Craftsmen:
2.8.1. The need to educate and train construction craftsmen
Education and training, as posited by Bokini (2005) compliments each other; while
education impacts knowledge, training inculcates skills into the receiver. Education
ensures background knowledge of a particular subject either in a public school,
college, university or in private institution. Training according to Wahab (1992) is
Mgt. Resp. & Orgn. x
Quality System x
Contract Review x
Document Control x
Purchasing x
Client Supplies
Process Control x x x x
Inspection& Testing x x
Insp./Measure/Testing x x
Insp./Test Status x x
Control Non-Conform x x
Corrective Action x x
Mat. Handlg /Storage x x
Quality Records x
Training x
Complaints x
50
an activity, which is concerned with making employee more articulate and efficient
in the performance of their current tasks, or in preparation for new types of job to
meet the dynamic needs of the organization. It is meant to develop mental ability,
dexterity and skill of personnel at all level.
Obiegbu (2002) stressed the need to maintain effective human resources in the
construction industry. He further stated that it involves first, an understanding of
the changes in the business environment as a result of many variables such as
economic situation, political trend and technological advancement that
continuously affect production. The second issue is the national approach to the
utilization of youth labour and maximization of technical and craftsmen cadre in
any market economy, which includes setting up adequate vocational training
programmes. Construction process demands efficient team, comprising
construction managers, engineers, technicians, craftsmen and artisans. Each of
these site personnel has specific and unique role to play in the entire execution of
construction project. The technicality of site work requires that every construction
worker must be practically productive, craftsmen inclusive. The craftsmen are
supposed to be workers of hand – on – tool group or the skilled operatives. The
dynamism of modern technology and the complexity of building infrastructure
designs demand that our present craftsmen should be effectively educated and
practically trained, and in adequate number for the following objectives:
i. To ensure standard and quality of construction projects
ii. To enhance early completion time of projects
iii. To reduce waste and make projects cost-effective
iv. To meet with the technological innovation in the construction industry.
v. To ensure adequate supply of skilled craftsmen and artisans
vi. To reduce supervision cost.
vii. To ensure good workmanship and proper finishing of construction work.
51
2.8.2 Mode of craftsmen education and training
Awe (2006) opined that the mode of education and training craftsmen and artisans
in Nigeria still follow the British education pattern largely due to their early rule of
the country.
In the pre-independent days, training of craftsmen is commenced using any of the
following programmes, which is still in use at present.
i. A formalized, full – time, five years vocational education in government trade
centres, established in capital cities and other districts or provisional
professional towns. Young boys and girls with qualification of standard six or
third year secondary grammar schools are admitted in levels 1 and 3 to train
in crafts courses such as carpentry and journey, block/brick laying and
concreting, painting and decoration, plumbing, welding, electrical wiring and
installation, automobile and plant maintenance, etc. At the completion of their
training they are registered to sit for City and Guilds of London craft
certificate examinations. The craft certificate exams are now conducted in
Nigeria by an education body called National Board for Technical and
Business Education, NABTEB at both ordinary and advanced levels.
ii. Government supervised apprenticeship scheme for craftsmen; usually
organized in public works departments, now ministry of works and housing,
under master craftsmen in various technical departments. The trainee must
have the basic education of standard six. At the end of the training which runs
in 3, 4 and 5 years, the trainee will be tested and certified with grade III, II or
I trade test certificate in any chosen trade.
iii. Private apprenticeship scheme, similar to the government scheme but are run
in private workshops and companies. The trainees are supervised by master
52
craftsmen in those establishments and are also prepared to take the same test
with their counterparts in the ministry of works.
2.8.3 Government Role in the Training of Craftsmen
Omeata (2000) cited a report on Second National Development Plan (1970 –
1974), and the Third National Development Plan of 1975 – 1980, whichy posited
that the attention of the Federal Government of Nigeria was drawn on the shortage
of technical manpower and more precisely that of the technicians and craft cadre.
In an attempt to reverse the situation, Federal Government adopted the following
measures.
i. Instituted a crash programme for which Nigerians were sent abroad to training
as technical teachers.
ii. The establishment of the National Board for Technical education (NBTE) to
coordinate and control technical education in the country.
iii. The establishment of Industrial Training Fund (ITF) in1971
iv. Encouragement plan for states to set up their own polytechnics by adopting a
policy of 50% matching grants on both re-current and capital expenditure of
the then thirteen state polytechnics.
v. Two tier system of Diploma award in polytechnics was abolished and
replaced by one tire system leading to the award of Nigeria National Diploma
(NND). This policy was later dropped in 1980 following protest by students
who preferred the former two-tier system.
vi. Free technical education introduced to encourage and stimulate increased
involvement.
vii. Review of the salary scale of polytechnics staff and the placement of holders
of HND in public service on salary grade level 8.
53
viii. Tertiary institutions were granted autonomy from ministry of education and
should be run by governing Councils.
The National policy on education of 1988 promulgates the establishment of
vocational education centers as the primary goals of;
i. Training manpower in the applied science, technology and business,
particularly at craft, advanced craft and technician levels.
ii. Providing the technical knowledge and vocational skills necessary for
agriculture, commerce and economic development.
iii. Training and imparting the necessary skills to individuals who shall be self-
reliant economically.
For the prime purpose of this study, which is centered on craft operatives, the
researcher has to examine further the role of the following government agencies
NBTE and ITF in the training of craftsmen.
2.8.3.1 NBTE Craft Training Scheme
According to the National Policy on Education of 1977 establishing NBTE with
subsequent review of 1981 and 1988, the board was primarily assigned the role of
controlling technical and business education in colleges and polytechnics, Nwosu
(2006). The other function of the board includes the following:
i. To advise the Federal Government on all aspect of technical education
outside the Universities and make recommendation on the national policy
necessary for the training of technicians, craftsmen and other skilled
manpower.
ii. To determine the skilled and middle level manpower needs of the country
after consultation with National Manpower Board (NMB) and Industrial
Training Fund (ITF). And recommend the programmes to be pursued by the
polytechnics and the establishment of new polytechnics.
54
iii. To inquire and advise the Federal Government on the financial needs of the
polytechnics and other technical instructions.
iv. To receive bulk grants from the Federal Government and allocate them to the
polytechnics and colleges on a formula.
v. To assist other agencies in channeling all the external aids to polytechnics in
Nigeria.
vi. To advise on, and take steps in harmonizing entry requirements and duration
of courses at technical institution.
vii. To lay down standards of skills to be attained and continually review such
standards according to the technological needs of the country.
viii. To review method of assessment of students and trainees and develop
a scheme of national certification for technical and craftsmen and other
skilled personnel in collaboration with the ministry of education and training
institution.
ix. To undertake periodic review of the terms and conditions of service of
personnel in the polytechnic and make recommendation thereon to the
Federal Government.
x. To collect data, analyze and publish information relating to technical and
vocational education.
xi. To accredit programmes of all the polytechnics, technical colleges and
vocational centers in the federation for the purpose of the award of
certificates and diplomas.
In order to achieve the above objectives, the board has four standing committees,
namely:
a. Planning and Development Committee (PDC).
b. Programme Evaluation and Certification Committee (PECC).
c. Finance and General Purpose Committee (FGPC).
55
d. Appointment and Promotion Committee (APC).
In the process of disbursing federal grants to the institutions by NBTE, especially
to the technical and vocational colleges, the board collaborates with States
Ministry of Education to convert part of their grants into equipments to be supplied
piece meal to colleges, Nwosu (2006).
2.8.3.2 ITF Craft Training Scheme
According to ITF bulletin, the Industrial training Fund, or simply called fund was
the first Nigerian Federal Government parastatal established for manpower training
and development. It was established by decree No 47 of 8th October 1971 in line
with post – independence drive for accelerated economic growth and development
during the second national development plan period of 1970-1974. The act further
stipulate that ITF was established with the specific mandate of transforming the
Nigerian economy from its predominant dependence on foreign expertise, to a state
of self – reliance through training and development of Nigerians who would be
competent to perform the specialized skills required to manage the essential sectors
of the Nigerian economy. In the mandate, the fund through its governing council
will formulate policies and make provision for;
i. Facilities for training of persons employed in the industry and commerce
ii. Approval of such courses and facilities provided by other persons.
iii. Consistent and regular consideration of operational areas of the industry and
commerce that requires special manpower development actions and
recommend the kind of training needed, the standards to be attained and to
ensure that such standards are met.
iv. Assisting persons in finding facilities for training and for employment in the
industry and commerce.
56
v. Consulting and assisting other persons to conduct researches into any matter
relating to training in industry.
ITF has seven full-fledged departments among, specialized professional and
occupational areas, headed by directors. One of such department that is concerned
with this research is the vocational and apprentice training department.
In pursuance of ITF policy of direct participation in the training and development
of industrial craftsmen, the department, referred as VAT was established in 1983
for the sole function of training and assisting other informal group in the training
of craftsmen and artisans in various trades. To carry out its duties, VAT, according
to ITF/ATM publication has three cardinal procedures, namely;
i. Skill improvement, updating and broadening courses at its vocational training
centre at Ikeja Lagos.
ii. Craft instructors’ courses in various trades at instructors training centre, ITC,
Kano.
iii. Direct collaboration with companies and industries in the in – house training
of craftsmen apprentices.
It may seem that ITF, through its VAT department has made commendable
progress in craft apprentice training in various trades, but its impact is yet to be felt
in the construction industry.
2.8.3.3 FMWH Training Schools
Federal Ministry of Work and Housing, through the high way department operates
three training schools for technicians and craftsmen in road construction and allied
works, Eliego (2000). Such schools are;
i. Lagos High Way Training Centre at Badagry
ii. Kaduna High Way Training Centre, Kaduna.
iii. Ugoneki High Way Training Centre, Edo State.
57
The syllabus used in training the students in these schools is constantly reviewed to
meet technological challenges ahead.
2.8.4 The Role of the Professional Bodies in the Training of Craftsmen
2.8.4.1 NSE and COREN Training Scheme
Nigerian Society of Engineers (NSE) and Council for the Regulation of
Engineering in Nigeria (COREN) have been on the forefront of training and
retraining of craftsmen in engineering crafts. Quoting Omeata (2000), one of the
management techniques and decision making that can contribute and lead us to the
most effective result in productivity and profitability in development pattern of the
society is “Training”. More importantly, is the training of engineering personnel.
One of the key duties of COREN as stated in decree No 55 of 1970 establishing the
council is to organize and supervise practical training of its categories of
engineering personnel, comprising.
i. Engineers – graduate of Universities
ii. Technologists – graduates of Polytechnics
iii. Technicians – graduate of Technical College
iv. Craftsmen – graduates of Trade Centres
According to Amusu (2002), COREN has the mandate to carry out the following
functions.
1. Establish technical workshops in collaboration with industrial
establishments.
2. Source for technical teachers or instructors trained to monitor performance
and award certificate of apprenticeship to all cadre of engineering crafts
apprentices.
3. Develop apprentice curriculum for industry for the different cadre, to
supplement the college effort
58
4. Enforce the establishment of practical training workshops in the industry
and ensure the maintenance of such workshops.
5. Facilitate control of apprentice training by establishing progress records
and test partition.
In recognition of every member of the engineering family COREN has approved
and coordinates the activities of various associations under the family such as
a. Nigerian Society of Engineer NSE
b. Nigerian Association of Technologist Engineers MATE
c. Nigerian Association of Craft Engineers NACE
In addition, COREN provides annual forum for all practitioners in engineering at
all levels to;
i. Evaluate matters of mutual interest relating to the profession
ii. Discuss intra and inter relationship between different cadres and the
Nigerian society.
iii. Assess and educate practitioners on various developments within the
engineering profession for a desirable standard of engineering practice.
iv. Award certificate to best performed engineer, technologist, technician
and craftsman of the year.
2.8.4.2 NIOB and CORBON Training Scheme
Nigerian Institute of Building (NIOB) and Council of Registered Builders of
Nigeria (CORBON), have recently joined craft training campaign. This may be due
to late promulgation of the Decree 45 establishing the council in 1989, which was
rectified in 1990 by ACT Cap 40. Before then, eminent professional builders have
aired their views regarding the need for urgent training of craftsmen to increase
their supply and productivity in the construction industry. The then president of the
institute, K.A. Wahab, commented that the effort of the Manpower Board through
59
strategic surveys have revealed manpower shortages in all aspect of the
construction industry. The worst hit areas being the intermediate personnel such as
building and civil engineering technicians, foremen, clerk of works and
supervisors, following by craftsmen, who were traditionally produced in the
informal training sector apprenticeship, Wahab (1990).
The Nigerian Institute of Building in her constitution stipulates that a committee on
craftsmen and artisans member cadre be constituted with the following objectives:
i. To determine and identity building craftsmen and artisans and establish the
interdependence of the various trades in the building industry.
ii. To review the criteria for registering building craftsmen and artisans under the
umbrella of the Nigerian Institute of Building in an appropriate cadre.
iii. To recommend training and retraining programme for building craftsmen and
artisans.
iv. To examine and make recommendation regarding the procedure for
registering craftsmen and artisans as members of the institute under an
appropriate cadre.
v. To present yearly report to the council on the affairs of building craftsmen
and artisans.
Challenged by shoddy work and poor finishing of buildings, rampant building
failures and incessant collapse of buildings, the institute through its national
council has developed and approved craftsmen/artisan registration policy;
curriculum for the training and retraining of craftsmen and artisans in line with
National Board for Technical Education (NBTE) syllabi and the need of the
industry – NBCS (2005). The policy further provides for conversion and
advancement of craftsmen along full corporate line, through appropriate
professional examinations. Recently in 2005, the Nigerian Institute of Building
convened building craftsmen summit in Lagos. The primary aim was to pool
60
together the available building craftsmen in the country, educate them on the new
trend in building activities and find solution to the shortage of artisans and
craftsmen that is obvious in the industry, especially fully trained ones. Any
professional builder, knowing what the situation is like in the construction industry
that is faced with inadequate craft operatives and shoddy work problem, will
commend the institute in her gesture to revive the craft group. It is better to wish
her well if only the idea will not be left to die a real death.
2.8.5 Private sector role in the training of craftsmen
This sector refers to construction companies of different sizes and individual
enterprises where the services of craftsmen and artisans are employed. In such
organizations bulk of their work are based on the efforts of these craftsmen. These
companies regularly accept young people who need apprenticeship craftsmen
training in order to meet their self-employment need. Aderoba (1994) opined that
bulk of craftsmen and artisans in Nigeria and indeed many African countries
receive their training from roadside local workshop on apprenticeship. These
workshops turn out mechanics, carpenters, bricklayers, electricians, plumbers,
painters, filters etc. in such a large scale that makes the output from the technical
colleges insignificant based on the survey he carried out at Ondo and Akure LGA
on Ondo State. He made the following discoveries;
i. About 92% of craftsmen and artisans practicing in the two towns received their
training from roadside workshops.
ii. The master craft trainers engage an average of four apprentices per master.
iii. The level of formal education of both the master craftsmen and the apprentices are
low
iv. Most of the trained artisans exhibit in – depth practical skill but with very poor
background in theoretical concept. They usually get embarrassed when confronted
61
with theoretical question. This limits their scope for improvement in new products
and services ideas.
v. Inspite of their number, they lack good knowledge of costing, book – keeping, job
planning and control.
vi. Government bodies pay very little attention to these roadside artisans and
apprentices, even though they account for more than 90% of the skilled workforce
in the country. They are not helped by way of formal training and other incentives
to improve their productivity and contribute effectively to the economy.
vii. Most of the artisans complained that they were not well paid when they work
for others, so they resort to self-employment.
The indigenous construction companies have not given proper attention to in-house
training of craftsmen and artisans, because of their quest for much profit. Only the
multinational construction firms who do not want to compromise qualify
workmanship in their projects, have given due attention to the recruitment of
qualified craftsmen and training of apprentices on various trades because of their
long term policies on in – house training of craftsmen and artisans. It could be said
that they have always maintained adequate resources of quality craftsmen in their
firms.
62
CHPATER THREE: METHODOLOGY
3.1 Research Design
The focus of this study is on the factors influencing construction craftsmen
productivity and quality of work in Nigerian indigenous construction companies.
The study investigated some of the factors using field survey research method,
carried out on indigenous construction companies.
3.2 Scope of Study
The study centered mainly on the managerial capabilities of the indigenous
construction company managers with respect to effective workforce planning and
supervision, workers motivation strategies and training arrangement for craftsmen,
which will ensure higher productivity and quality of work.
3.3 Population of study
The population of the study is the indigenous construction companies in the six
geo-political zones of Nigeria; Northeast, Northwest, North-Central, Southeast,
Southwest, South-South and Federal Capital Territory. Selected indigenous
construction companies in a representative state of each zone were considered as
population.
3.4 Sample and Sampling Techniques
The study used random sampling techniques in selecting the companies. Names of
ten indigenous construction companies in each state were listed on separate papers,
folded and thrown into separate black polythene bags. After thorough shaking of
the bags, ten of the folded papers were picked from each bag, one at a time and
names of the sample companies on the papers were listed, totaling 70 companies.
63
3.5 Instrument for Data Collection
A field survey instrument (see appendix A) was used in this study; through close
form structured questionnaire comprising twenty-five research questions, clearly
typed and printed in several copies.
3.6 Validation of Instrument
On the instruction and guidance of my supervisor, the questionnaire (comprising
25 structured questions) was framed on a minimum of five questions to each of the
research questions. This is to provide factual data to analyze the research questions
and hypothesis included in the study.
3.7 Method of Data Collection
The data collection instrument was administered to three categories of companies’
personnel; construction managers, site engineers and general foremen. The three
categories of personnel were chosen because of their direct involvement in
construction operations.
3.8 Method of Data Analysis
Collected data were organized and presented using statistical tables. The analyses
and testing of data were carried out with non-parametric inferential statistics, e.g
frequency, percentage, ranking and chi-square method.
3.9 Statistical Presentation of Data
Statistical tables below were designed and used to assemble the entire
questionnaire data received from fifty-two indigenous construction companies out
of seventy companies that were issued field research questionnaires. The
companies were those located and operating in the six geo-political zones of
Nigeria. Four categories of the companies’ personnel were administered with the
64
questionnaires; they are the General Managers, Construction Managers, Project
Engineers and General Foremen. A representative state was selected from each
zone for the field study: North-East Zone, Bauchi; North-West Zone, Kaduna;
North-Central Zone, Benue; South-East Zone, Enugu; South-West Zone, Oyo;
South-South Zone, Akwa Ibom and FCT, Abuja
This arrangement is required to classify all the collected data for further analysis
and testing of hypotheses.
Section one: Company profile
Table 3.1: Questionnaire No 1; Ownership composition of your company
Contractor Nigerian Ownership
Nigerian and Non Nigerian
Fully Foreign Ownership
Observed Frequency Total
Bauchi 3 0 0 3
Kaduna 7 0 0 7
Benue 6 0 0 6
Enugu 10 0 0 10
Oyo 6 0 0 6
Akwa Ibom 10 0 0 10
Abuja 10 0 0 10
Total 52 0 0 52
Table 3.2: Questionnaire No 2; Area of specialization of your company
Contractor Building Construction
Road Construction
Building And Road Construction
Observed Frequency Total
Bauchi 3 0 0 3
Kaduna 3 1 3 7
Benue 4 0 2 6
Enugu 3 2 5 10
Oyo 2 1 3 6
Akwa Ibom 4 2 4 10
Abuja 3 2 5 10
Total 22 8 22 52
Table 3.3: Questionnaire No3; Age of your company in construction
65
Contractor 15-20yrs 10-14yrs 5-9yrs Observed Frequency Total
Bauchi 1 2 0 3
Kaduna 2 3 2 7
Benue 2 2 2 6
Enugu 4 4 2 10
Oyo 3 3 0 6
Akwa Ibom 4 4 2 10
Abuja 4 5 1 10
Total 20 23 9 52
Table 3.4: Questionnaire No 4; Category of registration of your company.
Contractor
Federal State Federal & State Observed Frequency Total
Bauchi 0 2 1 3
Kaduna 0 4 3 7
Benue 0 3 2 6
Enugu 0 6 4 10
Oyo 2 2 3 6
Akwa Ibom 0 6 4 10
Abuja 5 0 5 10
Total 7 23 22 52
Table 3.5: Questionnaire No 5; Geographical location of your company
Contractor North East
North West
North Central
South East
South West
South South
FCT Observed Frequency Total
Bauchi 3 3
Kaduna 7 7
Benue 6 6
Enugu 10 10
Oyo 6 6
Akwa Ibom 10 10
Abuja 10 10
Total 3 7 6 10 6 10 10 52
Section Two: Construction planning, supervision and quality control
66
Table 3.6 Questionnaire No 6; What is the employment status of greater number of your craft
workers.
Contractor Staff Casual On Contact Observed Frequency Total
Bauchi 0 2 1 3
Kaduna 2 4 1 7
Benue 1 3 2 6
Enugu 2 5 3 10
Oyo 2 2 2 6
Akwa Ibom 3 5 2 10
Abuja 4 3 3 10
Total 14 24 14 52
Table 3.7: Questionnaire No 7; What is your company’s project planning set up.
Contractor Separate Department
Site Base Administrative Function
Observed Frequency Total
Bauchi 0 2 1 3
Kaduna 3 4 0 7
Benue 0 5 1 6
Enugu 3 7 0 10
Oyo 2 4 0 6
Akwa Ibom 4 6 0 10
Abuja 5 5 0 10
Total 17 33 2 52
Table 3.8 Questionnaire No 8; Who is the head of project planning in your company.
67
Contractor Engineer /Builder
General Foremen
Accountant Observed Frequency Total
Bauchi 0 3 0 3
Kaduna 3 4 0 7
Benue 2 4 0 6
Enugu 5 5 0 10
Oyo 3 3 0 6
Akwa Ibom 4 6 0 10
Abuja 7 3 0 10
Total 24 28 0 52
Table 3.9 Questionnaire No 9; What type of construction planning method is adopted in your
company.
Contractor Work Programming and Scheduling
Visual Estimation
Consultation with Workers
Observed Frequency Total
Bauchi 0 0 3 3
Kaduna 3 0 4 7
Benue 0 0 6 6
Enugu 4 0 6 10
Oyo 3 0 3 6
Akwa Ibom 4 0 6 10
Abuja 6 0 4 10
Total 20 0 32 52
Table 3.10: Questionnaire No 10; With regard to your present construction planning method,
estimate crafts workers output in your company.
68
Contractor High Average Below Average Observed Frequency Total
Bauchi 0 1 2 3 Kaduna 1 2 4 7
Benue 0 2 4 6
Enugu 2 3 5 10
Oyo 2 1 3 6
Akwa Ibom 3 2 5 10
Abuja 4 3 3 10
Total 12 14 26 52
Table 3.11: Questionnaire No 11; If the output of your craft workers is below average what is the
anticipated cause(s).
Table 3.12: Questionnaire No 12;What type of quality control method is adopted in your
company
Contractor Improper Planning and Supervision
Inadequate Funding
Poor health of Craftsmen
Observed Frequency Total
Bauchi 2 0 1 3
Kaduna 3 2 2 7
Benue 4 1 1 6
Enugu 4 3 3 10
Oyo 3 2 1 6
Akwa Ibom 4 4 2 10
Abuja 2 4 4 10
Total 22 16 14 52
69
Contractor Daily Supervision Check Lists and inspection tests
Daily Round Trip Observation by Manager/Foreman
Rely on Foreman Report
Observed Frequency Total
Bauchi 0 1 2 3
Kaduna 2
3
2
7
Benue 0 2
4
6
Enugu 1 3 6 10
Oyo 1 3 2 6
Akwa Ibom 2 4 4 10
Abuja 4 3 3 10
Total 10 18 24 52
Table 3.13: Questionnaire No 13; Please estimate your craftsmen quality of work with your
present method of quality control
Contractor High Average Below Average Observed Frequency Total
Bauchi 0 1 2 3
Kaduna 0 3 4 7
Benue 0 2 4 6
Enugu 1 4 5 10
Oyo 1 3 2 6
Akwa Ibom 1 4 5 10
Abuja 4 3 3 10
Total 7 20 25 52
Table 3.14: Questionnaire No 14: If the quality of work is below average, what could be the
cause(s)
Contractor Inadequate Control Method
Inadequate Equipment
Complex Work
Observed Frequency Total
70
Bauchi 2 0 1 3
Kaduna 4 1 2 7
Benue 4 2 0 6
Enugu 5 3 2 10
Oyo 4 1 1 6
Akwa Ibom 5 3 2 10
Abuja 4 3 3 10
Total 28 13 11 52
Table 3.15 Quetionnaire15; What method have you been using to determine the output of your
craftsmen
Contractor Comparing with Established Output Standards
Comparing with Previous Work
Physical Observation
Observed Frequency Total
Bauchi 0 2 1 3
Kaduna 2 2 3 7
Benue 1 2 3 6
Enugu 2 3 5 10
Oyo 1 2 3 6
Akwa Ibom 2 3 5 10
Abuja 4 3 3 10
Total 12 17 23 52
Section Three: Motivations of craft workers
Table 3.16 Questionnaire No 16; Please indicate the ratio of staff and casual craftsmen in your
company
Contractor 1: 2 1: 4 1: 6 Observed Frequency Total
Bauchi 0 0 3 3
Kaduna 1 3 3 7
71
Benue 0 3 3 6
Enugu 2 5 3 10
Oyo 0 4 2 6
Akwa Ibom 2 4 4 10
Abuja 5 3 2 10
Total 10 22 20 52
Table 3.17: Questionnaire No 17; What is the monthly salary for a staff craftsman in your
company
Contractor N18000-N20000 N 21000 - N25000 N26000-N30000 Observed Frequency Total
Bauchi 2 1 0 3
Kaduna 2 3 2 7
Benue 4 2 0 6
Enugu 2 5 3 10
Oyo 1 4 1 6
Akwa Ibom 1 5 4 10
Abuja 0 4 6 10
Total 12 24 16 52
Table 3.18: Questionnaire No 18; What is the daily wage for a casual craftsman employed in
your company
72
Table 3.19: Questionnaire No19; What Incentive packages have you adopted for your craft
workers
Contractor Free Transport and Medication
Overtime Payment and Bonus
Non Yet Observed Frequency Total
Bauchi 0 0 3 3
Kaduna 0 2 5 7
Benue 0 2 4 6
Enugu 0 2 8 10
Oyo 0 3 3 6
Akwa Ibom 2 4 4 10
Abuja 2 4 4 10
Total 4 17 31 52
Table 3.20: Questionnaire No 20; Please with the present wages, salaries and incentive packages
paid by your company estimate craft workers output
Contractor N1000 - N1200 N1300 - N1500 N1600 – N 2000 Observed Frequency Total
Bauchi 3 0 0 3
Kaduna 3 4 0 7
Benue 4 2 0 6
Enugu 0 5 5 10
Oyo 2 4 0 6
Akwa Ibom 0 6 4 10
Abuja 0 2 8 10
Total 12 23 17 52
73
Contractor High Average Below Average
Observed Frequency Total
Bauchi 0 1 2 3
Kaduna 0 2 5 7
Benue 0 2 4 6
Enugu 0 5 5 10
Oyo 0 3 3 6
Akwa Ibom 1 5 4 10
Abuja 2 5 3 10
Total 3 23 26 52
Table 3.21: Questionnaire No 21; If the output of craft workers is still below average, what is the
anticipated cause(s).
Contractor Lack of Materials
Inadequate Wage And Incentives
Idleness Among Workers
Observed Frequency Total
Bauchi 1 2 0 3
Kaduna 2 3 2 7
Benue 2 3 1 6
Enugu 3 4 3 10
Oyo 2 3 2 6
Akwa Ibom 4 4 2 10
Abuja 2 3 5 10
Total 16 21 15 52
Section four: Crafts workers Recruitment and Retraining
Table 3.22: Questionnaires No 22: What is your recruitment source(s) for craft workers.
Contractor College And Advert
Personal Recommendation
Labour Shop Observed Frequency Total
74
Bauchi 0 1 2 3
Kaduna 0 3 4 7
Benue 0 2 4 6
Enugu 2 3 5 10
Oyo 1 2 3 6
Akwa Ibom 3 4 3 10
Abuja 4 2 4 10
Total 10 17 25 52
Table 3.23: Questionnaire No 23; What is the minimum qualification for your craft workers.
Contractor Trade Tested
Apprentice Testimonial
Previous Work Participation
Observed Frequency Total
Bauchi 0 0 3 3
Kaduna 2 3 2 7
Benue 1 2 3 6
Enugu 2 2 6 10
Oyo 2 2 2 6
Akwa Ibom 3 3 4 10
Abuja 5 2 3 10
Total 15 14 23 52
Table 3.24: Questionnaire No 24: What is your training or retraining scheme for craftsmen in
your company?
Contractor Apprenticeship Scheme
Short Course at Technical Colleges
No Training Scheme at Present
Observed Frequency Total
Bauchi 3 0 0 3
Kaduna 3 0 4 7
75
Benue 1 0 5 6
Enugu 0 0 7 10
Oyo 2 0 4 6
Akwa Ibom 0 0 I0 10
Abuja 0 0 10 10
Total 9 0 43 52
Table 3.25: Questionnaire 25; With the present level of qualification and training of your
craftsmen estimate their efficiency in terms of output and quality of work
Contractor High Average Below Average
Observed Frequency Total
Bauchi 0 1 2 3
Kaduna 0 2 5 7
Benue 0 2 4 6
Enugu 1 3 6 10
Oyo 1 2 3 6
Akwa Ibom 1 3 6 10
Abuja 3 4 3 10
Total 6 17 29 52
3.10 DATA ANALYSIS
Frequency Ranking and Chi-Square statistics were used to analyze the table data
that relate to the research questions and for the testing of the hypotheses.
76
Research Question 1
Can improper planning and poor supervision greatly affect the productivity of
construction workers in our indigenous construction companies?
Table 3.26 Analysis (adopted from table 4.11) on the factors that can directly affect productivity
of craft workers employed in indigenous companies
Factor/Response Opinion Frequency Percentage Ranking
Improper planning and supervision 22 42.31 1
Inadequate funding 16 30.77 2
Poor health of craft workers 14 26.92 3
Total 52 100%
Figure 3.1 Graphical analysis of data
From the factor ranking on the table3.26, it has become evident that the 1st, which
is improper planning and supervision, is the greatest factor among others that
affects the productivity of construction workers in indigenous construction
companies in Nigeria
77
Research Question 2
Can poor wages and absent of motivational incentives greatly affect the
productivity of construction workers in our indigenous construction companies?
Table 3.27 Analysis (adopted from table 4.19) on the type of motivational incentives policies
indigenous contractors apply to their craft workers
Response Opinion Frequency Percentage Ranking
Free transportation and medical treatment only 4 7.69 3
Overtime payment only 17 32.69 2
No incentive and wage increment scheme at present 31 59.62 1
Total 52 100
Figure 3.2 Graphical analysis of data
From the factor ranking on the table 3.27, it has also become evident that the 1st
that is no incentives and poor wage among other factors can greatly affect the
productivity of construction workers in indigenous construction companies in
Nigeria
78
Research Question 3
Will inadequate education and training greatly affect the quality of work and
output of craft workers in our indigenous construction companies?
Table 3.28 Analysis (adopted from table 4.23) on the type of vocational qualification possessed
by most craft workers employed by indigenous contractors
Response Opinion Frequency Percentage Ranking
Trade tested only 15 28.85 2
Apprenticeship testimonial only 14 26.92 3
Previous work participation only 23 44.23 1
Total 52 100
Figure 3.3 Graphical analysis of data
From the factor ranking on the table 3.8, it can be proved that the 1st, which is the
use of previous work participation only as basic qualification, is inadequate and
will greatly affect the quality of work and productivity of craft workers in
indigenous construction companies in Nigeria
79
Testing Null Hypothesis 1
H01: Improper planning, supervision and control of craftsmen activities on
construction site significantly affect their productivity and quality of work in
indigenous construction companies in Nigeria.
Table 3.29 Testing (adopted from table 4.11) on the type of factors that can affect productivity of
craft workers employed in indigenous construction companies
Figure 3.4 Graphical analysis of data
Total sampled opinion / Respondents = 52
Observed frequency O range from 0 to 10
Expected frequency E = row total x column total Grand total
Contractor Inadequate Planning
and Supervision
Inadequate
Funding
Poor health of
Craftsmen
Observed
Frequency Total
Bauchi 2 0 1 3
Kaduna 3 2 2 7
Benue 4 1 1 6 Enugu 4 3 3 10 Oyo 3 2 1 6
Akwa Ibom 4 4 2 10
Abuja 2 4 4 10 Total 22 16 14 52
80
E11 = 3X22 = 1.27 E12 = 3X16 = 0.92 E13 = 3X14 = o.81 52 52 52 E21 = 7X22 = 2.96 E22 = 7X16 =2.15 E23 = 7X14 = 1.89 52 52 52 E31 = 6X22 =2.54 E32 = 6X16 = 1.85 E33 = 6X14 = 1.62 52 52 52 E41 = 10X22 = 4.23 E42 = 10X16 = 3.08 E43 = 10X14 = 2.69 52 52 52 E51 = 6X22 =2.54 E52 = 6X16 = 1.85 E53 = 6X16 = 1.62 52 52 52 E61 = 10X22 = 4.23 E62 = 10X16 =3.08 E63 = 10X14 =2.69 52 52 52 E71 = 10X22 = 4.23 E72 = 10X16 = 3.08 E73 = 10X14 = 2.69
Table 3.30 Testing of hypotheses 1
Cell Oi Ei Oi – Ei ( Oi – Ei)2
(Oi – Ei)2 / Ei
E11 2 1.27 0.73 0.53 0.42
E12 0 0.92 -0.92 0.85 0.92
E13 1 0.81 0.19 0.04 0.05
E21 3 2.96 0.04 0.00 0.00
E22 2 2.15 -0.15 0.03 0.01
E23 2 1.89 0.11 0.01 0.01
E31 4 2.54 1.46 2.13 0.84
E32 1 1.85 -0.85 0.72 0.39
E33 1 1.62 -0.62 0.38 0.24
E41 4 4.23 -0.23 0.05 0.01
E42 3 3.08 -0.08 0.01 0.00
E43 3 2.69 0.31 0.10 0.04
E51 3 2.54 0.46 0.21 0.08
E52 2 1.85 0.15 0.02 0.01
E53 1 1.62 -0.62 0.38 0.24
E61 4 4.23 -0.23 0.05 0.01
E62 4 3.08 0.92 0.85 0.28
E63 2 2.69 -0.69 0.48 0.18
E71 2 4.23 -2.23 4.97 1.18
E72 4 3.08 0.92 0.85 0.28
E73 4 2.69 1.31 1.72 0.64
5.83
Calculated Chi-Square X2 = ∑ (Oi – Ei)2 / Ei
= 5.83
Degree of freedom df = (R-1)(C-1)
R = No of rows, C = No of columns df = (7-1)(3-1) = 12
81
Level of significant = 5% or 0.05
From Chi- Square Table, X20.05 = 23.69
X2
c = 5.83< 21.026 ie significant
Based on the result above, X2c significant, we therefore accept the null hypothesis
HO1 which state that improper planning, supervision and control of craft workers
activities on construction site significantly affect their productivity in indigenous
construction companies
Testing Null Hypothesis 2
H02: Poor wages and inadequate motivational incentives significantly affect the
productivity and quality of work of craftsmen in indigenous construction firms in
Nigeria.
Table 3.1 Analysis (adopted from table 4.19) on the output of craft workers based on the present
wages, and incentive policy
Respondents Free
Transport
and
Overtime
Payment and
Bonus
Non
incentives Yet
Observed Frequency
Total
Bauchi 0 0 3 3 Kaduna 0 2 5 7 Benue 0 2 4 6
Enugu 0 2 8 10 Oyo 0 3 3 6
Akwa Ibom 2 4 4 10 Abuja 2 4 4 10 Total 4 17 52
82
Figure 3.5 Graphical analysis of data
Total sampled opinion / Respondents = 52
Observed frequency O range from 1to 10
Expected frequency E = row total x column total Grand total Table 3.2 Testing of hypotheses 2
Cell Oi Ei Oi – Ei ( Oi – Ei)2
(Oi – Ei)2
/ Ei
E11 0 0.23 - 0.23 0.05 0.22
E12 0 0.98 - 0.98 0.96 0.98 E13 3 1.79 1.21 1.46 0.82
E21 0 0.54 - 0.54 0.29 0.54
E22 2 2.29 - 0.29 0.08 0.35 E23 5 4.17 0.83 0.69 0.17
E31 0 0.46 - 0.46 0.21 0.46 E32 2 1.96 0.04 0.00 0.00
E33 4 3.58 0.42 0.18 0.05
E41 0 0.77 - 0.77 0.59 0.77 E42 2 3.27 - 1.27 1.61 0.49
E43 8 5.96 2.04 4.16 0.70 E51 0 0.46 - 0.46 0.21 0.46 E52 3 1.96 1.04 1.08 0.55
E53 3 3.58 - 0.58 0.34 0.10 E61 2 0.77 1.23 1.51 1.96 E62 4 3.27 0.73 0.53 0.16
E63 4 5.96 - 1.96 3.84 0.64 E71 2 0.77 1.23 1.51 0.10 E72 4 3.27 0.73 0.53 0.16 E73 4 5.96 - 1.96 3.84 0.64
10.32
83
Calculated Chi-Square X2 = ∑ (Oi – Ei)2 / Ei = 10.32
Degree of freedom df = 12
Level of significant = 5% or 0.05
From Chi- Square Table, X20.05 = 23.69
X2
c = 10.32< 21.026 ie significant
Based on the result above, X2c significant, we therefore accept the null hypothesis
HO2 which posit that poor wages and inadequate motivational incentives
significantly affect the productivity of craft workers in indigenous construction
companies in Nigeria
Testing Null Hypothesis 3
H03: Inadequate education and vocational training of craftsmen significantly affect
their quality of work in indigenous construction companies in Nigeria.
Table 3.33 Analysis (adopted from table 4.23.) on the quality of work and output of craft
workers with their present qualifications and training
Respondents Trade
Tested
Apprentice
Testimonial
Previous Work
Participation
Observed Frequency
Total
Bauchi 0 0 3 3
Kaduna 2 3 2 7
Benue 1 2 3 6 Enugu 2 2 6 10 Oyo 2 2 2 6
Akwa Ibom 3 3 4 10
Abuja 5 2 3 10
Total 15 14 23 52
84
Figure 3.6 Graphical analysis of data
Total sampled opinion / Respondents = 52.
Observed frequency O range from 1to 10
Expected frequency E = row total x column total Grand total
Table 3.34 Testing of hypotheses 3
Cell Oi Ei Oi – Ei ( Oi – Ei)2
(Oi – Ei)2
/ Ei
E11 0 0.86 - 0.86 0.74 0.86
E12 0 0.64 - 0.64 0.41 0.64 E13 3 1.50 1.50 2.25 1.50 E21 2 2.02 - 0.02 0.00 0.00
E22 1 1.48 - 0.48 0.23 0.16 E23 4 3.50 0.50 0.25 0.07 E31 1 1.73 - 0.73 0.53 0.31
E32 1 1.27 -0.27 0.07 0.06
E33 4 3.00 1.00 1.00 0.33
E41 2 2.89 - 0.89 0.79 0.27 E42 2 2.12 - 0.12 0.01 0.01
E43 6 5.00 1.00 1.00 0.20 E51 2 1.73 0.27 0.07 0.04
E52 2 1.27 0.73 0.53 0.42 E53 2 3.00 - 1.00 1.00 0.33
E61 3 2.89 0.11 0.01 0.00
E62 3 2.12 0.88 0.77 0.36 E63 4 5.00 - 1.00 1.00 0.20
E71 5 2.89 2.11 4.45 1.54 E72 2 2.12 - 0.12 0.01 0.01
E73 3 5.00 -2.00 4.00 0.80
8.11
85
Calculated Chi-Square X2 = ∑ (Oi – Ei) 2 / Ei
= 8.11
Degree of freedom df = (R-1)(C-1)
df = (7-1)(3-1) = 12
Level of significant = 5% or 0.05
From Chi- Square Table, X20.05 = 23.69
X2
c = 8.11< 21.026 ie significant
Based on the result above X2c significant, we therefore accept the null hypothesis
HO3 which implies that inadequate education and vocational training of craft
workers significantly affect their quality of work in indigenous construction
companies in Nigeria
86
CHAPTER FOUR: RESULTS AND DISCUSSION
4.1 RESULTS OF FIELD SURVEY
1. All the construction companies investigated were fully Nigerian owned or
indigenous and 42.3% of them operate as building/civil engineering companies,
another 42.3% as building constructors, and the remaining 15.4% as road
construction companies.
2. Majority of the indigenous construction companies have been in operation for
more than ten years and are registered either with the federal, state or both
3. Majority of the indigenous construction firms employs greater number of
craftsmen on casual basis.
4. More than half of the companies investigated carry out their construction
planning on the site and majority of the planners are General Foremen.
5. 62% of the companies carryout their construction planning by consultation with
workers, only 38% use work programming and scheduling.
6. Majority of the indigenous companies indicated that with their present
construction planning method the output of their craftsmen is still below average
and gave their reason as inadequate planning and supervision, while the second
group says it is inadequate finding.
7. 46% of the indigenous construction companies carry out work quality control by
relying on foremens’report, 34% rely on the managers’ round trip observation
reports, and only 20% use daily supervision check list and inspection tests.
8. Greater number of the companies indicated that with their present method of
quality control the quality of their job is still below average and gave their reasons
as inadequate training of craft workers
87
9. 44% of the companies evaluates daily output of their craftsmen by physical
observation, 32% evaluates by comparing with previously completed work, while
the remaining 24% evaluates by comparing with established output standards.
10. Majority of the indigenous companies pay their staff craftsmen less than
N35000 monthly and pay casual craftsmen less than N2000 per day.
11. 62% of all the indigenous companies have no immediate plan to use incentive
packages to motive their crafts workers while only 32% could pay overtime.
12. The same majority indicated that their craftsmen output is below average and
gave their reasons as inadequate wages and incentives.
13. Greater number of the companies recruit their craftsmen through labour shops
and they use previous job participation as qualifications.
14. 82% of the companies indicated that they have no immediate training or
retraining scheme for their crafts workers.
15. Majority of the indigenous companies finally indicated that the efficiency of
their craft workers in terms of productivity and quality of work is below average
and the cause is inadequate craft training
4.2 DISCUSSION OF RESULTS
Items 2 and 3 of the results of findings imply that the indigenous construction
companies have been in the business for upwards of twenty years and they still
employ more causal craftsmen than staff craftsmen. This casual method of
employing craftsmen could not guarantee quality work and higher productivity.
Items 2 and 6 indicated that majority of indigenous construction companies
carryout their construction planning on site through their general foremen and by
consultation with workers.. This looks very unprofessional and has the possibilities
of achieving low output and consequently leading to waste of labour resources and
production time. Greater number of the contractors agreed to these possibilities.
88
Items 7 and 8 pointed out that greater number of the contractors rely on the
foremen and manager’s observation report as a means of controlling quality of
work instead of using checklist and inspection test. The result of such method will
be poor quality of job all through the project, in spite of low training of workers.
Item 9 indicated that most of the contractors evaluate their workers output by
observation and comparing with previous works, which is also unprofessional and
cannot guarantee steady improvement or aid proper planning.
Items 10,11and12, reported that greater number of the indigenous companies pay
between N1000 and 1500 per day to the causal craftsmen and less than 3500
monthly to the staff craftsmen and without appreciable incentive scheme. It is very
clear that the wages are low for the crafts workers, considering the present cost of
living in the country. The result of this poor condition is low morale, and low
output of work, which they all confirmed. Also the companies stand the chance of
losing good craftsmen any time.
Items 13 and 14 stated the labour shop method which most of the companies use in
recruiting craftsmen of low training and their hesitant attitude to train them further.
It is obvious that these contractors have not accepted the fact that construction is
highly technical, and production oriented business, which must be done with the
target of meeting the needs of clients, in terms of quality and value. Only efficient
and well-trained craftsmen under the supervision of professional managers can
achieve such tasks. However the contractors finally agree that untrained craftsmen
will always produce below expectation.
89
CHAPTER FIVE: CONCLUSION AND RECOMMENDATIONS
5.1 CONCLUSION
In every economic and management process, higher productivity is matched with
reward or profit. Productivity is a measure of individual or collective performance
of resource input in an organization. Craftsmen working on a construction site are
seen as part of the labour resource input and are expected to be productive. With
the research findings above it is now obvious that our indigenous construction
contractors and their craft workers are not really productive for the following
reasons;
i- Improper project planning and supervision of craft workers which could
not ensure high productivity. This was further confirmed by the accepted null
hypothesis Ho1.
ii- Inadequate or total absent of motivational incentives for craft workers
which also limited their productivity. The accepted null hypothesis Ho2
proved this assertion.
iii - low vocational training of recruited craftsmen with no provision of
retraining them resulting to poor quality of work. Again this situation was
confirmed by the accepted null hypothesis Ho3.
In view of these revealed points, I finally posit that the productivity and quality of
work of craftsmen working in indigenous construction companies, in nearly all the
states of the federation is below standard.
90
5.2 RECOMMENDATIONS OF THE STUDY
Based on the above research findings, analysis and tests, decision models below,
were developed for indigenous construction contractors to adopt and improve their
craft workers productivity and quality of work.
Affecting Factor: Improper planning and supervision
Improvement Strategies:
o Establish a project-planning unit to be headed by a qualified and experienced construction engineer/manager.
o The planning engineer must always use modern planning tools, which include method statement, labour standard, CPM analysis, work programme, labour and materials schedule charts.
o Site engineers must be furnished with work programme, labour and materials schedules. o Site engineers must always stay on site to direct the craft workers on every section of
work till day work is over. o Engineers must use checklist to supervise work. o Engineers must conduct tests on materials and equipments before use. o Keep records of daily and weekly labour output. o Always compare output with programme of work and correct any delay or deviation. o Use effective communication methods onsite
Affecting Factor: Non use of adequate incentives
Improvement Strategies:
o Provide a policy to motivate site workers with incentives. o Use financial and non-financial incentives to motivate site workers always. o Maintain higher ratio of permanent craft workers than casuals. o Pay craft workers adequately and on time
Affecting Factor: Poor training of craft workers.
Improvement Strategies:
o Ensure that every craft worker on site is trade tested or with approved vocational trade certificate.
o When necessary retrain each craftsman for higher productivity and quality of work
This study could not be exustive of the problem factors affecting construction
workers productivity and quality of work in the industry and therefore the
following further studies are suggested;
91
1) The impact of poor welfare management on the productivity of construction
workers in a large size construction company.
2) The effect of inadequate communication system on construction workers
productivity and quality of work.
3) The need for intensive training and retraining of craftsmen for higher
productivity in the construction industry
5.3 LIMITATIONS OF THE STUDY
In the course of carrying out this study, some limitations were encountered and
they include the followings;
1) The time needed to complete this study was short, when compared with the
content and geographical coverage of the study.
2) Some respondents were not very free with their responses as many thought
the questionnaire was to their disadvantages.
3) Transportation and lodging costs in the far northern states were setbacks to
the study and this affected the rate of return of the instrument
92
REFERENCES
Aderoba Adeyemi: (1994) Extension Education for Roadside Apprentices; Journal of Training and Development TRADE. Vol. 1No 2PP 19 ITF Jos Nigeria
Adrain J. J. (1282) Construction Estimating; an Accounting and Productivity
Approach, Prentice-Hall Reston Publishing Co. Virginia Alfred L E :( 1988) Construction Productivity, Book Company, New York Amusu I (2000) Theoretical Training for Engineering Personnel; 10th Engineering
Assembly, Abuja Nigeria Andesons S P, Wood head RW: (1981) Project Manpower . John Wiley & Sons Austen A.D :( 1994) Managing Construction Project. I LO Production, Geneva Awe M.E (2006). Strategies for Functional Technical Education and Training of
Skilled Craftsmen. The Builders Focus pp 33 NAOBS. Bamisile A. (2004). Building Production Management. Foresight Press Ltd Lagos Bennett I: (1985) Construction Project Management Butterworth’s, London Bokini S.K. (2005) Skill Acquisition and Development for Craftsmen and Artisans;
The Professional Builder NIOB Journal, pp 100 Calvert R.E.(2000) Introduction to Building Management Newness Butterworth,
London Chitkara. KK: (2006) Construction Project Management New Delhi, Tata Eliego C. F. (2000). Practical Training for Engineering Personnel; 10th Engineering
Assembly Abuja Nigeria. Harris F& MacCffer R. (2001) Modern Construction Granada, London. ITF (2007) Manpower Training and Development,
Jeremaih P. (2012). National Productivity Data. An FRCN Documentary Report
93
John J.E: (1981) Site Control of Materials Butterworth’s, London
Kadyali L R and Lal N.B (2008) Principles and Practices in Highway Engineering. Khana Publishers. New Delhi.
Kerzner H. (1998) Project Management; A System Approach to Planning,
Scheduling and Controlling.Van Nostrand Rem Hold, New York. Kharband O.B. (1980) Project Control in Action. Gower Publishing Co.
Hampshire England. Lewis I :(1991) Cited by Matt. Carpenter; Improving Productivity of Construction
Workers; Tulio.sulbaran@usm.edut. NIOB (2005) Nigerian Building Craftsmen Summit Publication Nunnally S.w. (1977) Construction Methods And .Management Prentice –Hall,
New Jersey Nwosu C.C. (2004) Teaching Technical Subjects in Technical Colleges in Afikpo
North L.G.A; Problem and Solution. TTC/VTE Project Report. Abia State College of Education (Technical) Arochukwu
O’ Brien JJ and Zill R,G.(1971) Constructor Management Handbook, McGraw-
Hill NY Obiegbu M. E (2002) Training and Retraining of Craftsmen for Nigerian
Construction Industry, The Millennium Challenge; The Professional Builders NIOB, Journal pp 57
Omeata .E C: (2000) Cost and Funding of Training for Engineering personnel;
10th Engineering Assemble, Abuja Nigeria Peter G. (1981) Project Management Control. Construction Press, London. Udegbe M I (2005) Labor Force Output on Plastering Activity in Edo State; The
Professional Builder, NIOB Journal pp 34 Ujega E.T. (2000) Academic &Practical Training for Engineering Personnel; 10th
Engineering Assembly, Abuja Nigeria
94
Wahab K A (1992) Satisfying the Training Needs of Management and Staff in the
Construction Industry Effective Contract Management in the Construction Industry NIOB Journal pp 80
Wahab KA (1990) Manpower Development and Training for the Construction
Industry: The Registered Builders’ Journal NIOB PP 14
95
APPENDIX A
Department of Civil Engineering
Faculty of Engineering University of Nigeria, Nsukka
March 2011
Dear Sir/Madam,
RESEARCH QUESTIONNAIRE
We are delighted to request for your kind response to the attached questionnaire. It
is part of our research work on the ‘Factors affecting the productivity and
quality of work of construction workers in Nigerian indigenous construction
companies.
The study is purely an academic exercise in partial fulfillment for the award of a
Master of Engineering Degree in Materials and Construction Engineering. It is
therefore hoped that the information you will provide in this questionnaire will
make the study worthwhile and also useful to the department.
Your response shall be well appreciated and treated confidentially.
Yours faithfully,
C.F.M. Chukwuji Prof. (Engr.) O.O. Ugwu
Reg. No: PG/MEng/09/50669 (Supervisor)
96
Name and address of company……………………………………………………..
………………………………………………………………………………………
Name of respondent ………………………………………………………………..
Qualification(s) of respondent………………………………………………………
Position held in the company ………………………………………………………
(General Manager, Construction Manager, Project Engineer, General foreman)
Section One: Company Profile (Tick as applicable)
1. Ownership composition of your company.
[ ] Fully Nigerian Ownership
[ ] Nigerian and Non Nigerian ownership
[ ] Fully foreign ownership
2. Area of specialization of your company
[ ] Building construction only
[ ] Highway/Road construction only
[ ] Building and Road construction
3. Age of your company in construction
[ ] 15 years and above
[ ] 10 – 14 years
[ ] 5 – 9 years
4. Category of registration of your company
[ ] Federal
[ ] State
[ ] Federal & State
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5. Geographical location of your company in Nigeria (please specify)
[ ] North-East …………………………….................................
[ ] North-West …………………………………………………
[ ] North-Central ………………………………………………..
[ ] South-East …………………………………………………..
[ ] South-West ………………………………………………….
[ ] South-South …………………………………………………
Section Two: Construction Planning, Supervision and Quality Control
6. What is the employment status of greater number of your craft workers.
[ ] Staff
[ ] Casual
[ ] Contract staff
[ ] All of the above
7. What is your company’s project planning set up
[ ] Separate department
[ ] Site base
[ ] Administrative function
[ ] Others (please specify) ……………………………………………...
8. Who is the head of project planning in your company
[ ] Engineer/Construction Manager
[ ] Foreman
[ ] Accountant
[ ] Others (please specify) ……………………………………………...
9. What type of construction planning method is adopted in your company.
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[ ] Work programming and scheduling
[ ] Visual estimation
[ ] Consultation with workers
[ ] Others (please specify) ……………………………………………
10. With regard to your present construction planning method, estimate crafts
output in your company.
[ ] High
[ ] Average
[ ] Below average
[ ] Others (please specify)…………………………………………..
11. If the output of your craft workers is below average what is the anticipated
cause(s).
[ ] Improper planning and supervision
[ ] Inadequate Funding
[ ] Poor health of craftsmen
[ ] Others (please specify) ……………………………………………...
12. What type of quality control method is adopted in your company
[ ] Daily supervision with check lists
[ ] Daily round trip observation by manger/foreman
[ ] Rely on foreman report
[ ] Others (please specify) ……………………………………………...
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13. Please estimate your craftsmen quality of work with your present method of
quality control.
[ ] High
[ ] Average
[ ] Below average
[ ] Others (please specify)…………………………………………..
14. If the quality of work is below average, what could be the cause(s)
[ ] Inadequate control method
[ ] Inadequate equipment
[ ] Complex work
[ ] Others (please specify)…………………………………………..
15. What method have you been using to determine output of your craftsmen
[ ] Comparing with established output standard
[ ] Comparing with previous work
[ ] Physical observation
[ ] Others (please specify) …………………………………………….
Section Three: Motivation of crafts workers
16. Please indicate the ratio of staff and casual craftsmen in your company
[ ] 1:2
[ ] 1:4
[ ] 1:6
[ ] Others (please specify)…………………………………………..
17. What is the monthly salary for a staff craftsman in your company
100
[ ] N18, 000 – N 20000
[ ] N21, 000 - N 25000
[ ] N26, 000 - N30000
[ ] Others (please specify) ……………………………………………..
18. Daily wage for a casual craftsman you employ
[ ] N1,000 – N1200
[ ] N 1,300 – N1500
[ ] N 1,600 – N2000
[ ] Others (please specify) …………………………………………….
19. What incentive packages have you adopted for the crafts workers
[ ] Free transport and medication
[ ] Overtime payment and bonus
[ ] None yet
[ ] Others (please specify) ……………………………………………
20. Please, with the present wages, salaries and incentive packages paid by your
company estimate craftsmen output.
[ ] High
[ ] Average
[ ] Below average
[ ] Others (please specify)…………………………………………..
21. If the output of craft workers is still below average, what is the anticipated
cause(s).
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[ ] Lack of materials
[ ] Inadequate wages and incentives
[ ] Idleness among workers
[ ] Others (please specify) ………………………………………………
Section Four: Craftsmen recruitment and training
22. What is your recruitment source(s) for crafts workers
[ ] College contact/advert
[ ] Personal Recommendation
[ ] Labour shop
[ ] Others (please specify) ……………………………………………..
23. What is the minimum qualification for your crafts workers
[ ] Trade tested
[ ] Apprentice testimonial
[ ] Previous work participation
[ ] Others (please specify) ……………………………………………..
24. What is your training or retraining scheme for craftsmen in your company.
[ ] Apprenticeship scheme
[ ] Short courses at technical colleges
[ ] No training scheme at present
[ ] Others (please specify) ……………………………………………..
25. With the present level of qualification and training of your craftsmen estimate
their efficiency in terms of output and quality of work
[ ] High
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