sab 3353 reinforced concrete design i -...
TRANSCRIPT
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SAB 3353
REINFORCED CONCRETE DESIGN I
DR. IZNI SYAHRIZAL BIN IBRAHIM
FACULTY OF CIVIL ENGINEERING
UTM
ROOM: M47-126
EMAIL: [email protected]
Course Learning Outcome (CO)
Note : (A – Assignment; T – Test ; PR – Project ; Q – Quiz; HW – Homework ; Pr – Presentation; F – Final Exam)
CO Course Learning Outcomes Programme Outcome(s)
Taxonomies and
Soft-Skills
Assessment Methods
CO1
Define and describe the concept, procedure and objective of reinforced and prestressed concrete design.
PO1 C2 A, T, F
CO2
Analyze and design of reinforced concrete beams and slabs, and produce detailing for the elements.
PO3 C5, A3 A, T, F
CO3
Propose a suitable structural layout plan for typical building floors and prepare a concise and optimum beam and slab design calculation from a given architectural drawing and produce detailing for the elements.
PO3 C4, P4, A3 PR
CO4 Apply ethical standard in professional practice and social interactions.
PO10 P5, A2, EM3 PR
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PO1
Ability to acquire knowledge of science and civil
engineering principles.
Lectures, tutorials, seminars, laboratory works, directed
reading, independent study, active learning.
Examinations, laboratory reports, presentations, assignments,
problem-based exercises, project reports.
PO2
Ability to use the techniques, skills and modern civil
engineering tools.
Lectures, tutorials, computer hands-on sessions, laboratory
works, industrial training, surveying camps.
Examinations, laboratory reports, presentations, assignments,
problem-based exercises, project reports, design tasks, simulation
exercises, industrial training reports.
PO3
Ability to analyse, interpret, develop and conduct
experiments; and design components, systems, or
processes.
Project supervision, lectures, tutorials, laboratory works, directed reading, simulation exercises, computer-based
exercises, independent study, problem-based learning.
Final Year Project reports, project reports, design tasks, examinations, laboratory reports, presentations,
assignments.
Code Intended Learning
Outcomes
Teaching and
Learning Methods Assessment
PO10
Ability to apply high ethical standards in
professional practice and
social interactions for sustainable
development.
Final year projects, Laboratory works,
Industrial training, surveying
camps.
Written assignments, laboratory
reports, essays, final year project
reports, Industrial training report.
Code Intended Learning
Outcomes
Teaching and
Learning Methods Assessment
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ATTENDANCE The student should adhere to the rules of attendance as stated in the University Academic Regulation: • Student must attend NOT less than 80% of lecture hours as required for the subject. • The student will be PROHIBITED from attending any lecture and assessment activities upon failure to comply the above requirement. Zero mark will be given to the subject.
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ATTENDANCE
Be ON TIME during class. I will not tolerate
LATE COMERS !!!
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To ensure the structure is safe and suitable for occupancy with minimum cost
Material, type, size and
configuration of the structure
Calculation Drawing detailing
a. Fitness for purpose
b. Safety and reliability
c. Economy
d. Maintainability
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Phase 1 Planning
Phase 2 Structure analysis
Phase 3 Member design
Client summary Imagination
Economic factor
Lab test
Environmental factor
Site survey
Equilibrium
Deflection
Stress & strain
Elastic modulus
Forces in member
Codes of practice
Drawing detailing
Phase 4 Construction
Project manager
Architect
Consulting engineer
Quantity surveyor
Civil and structural engineer
Mechanical and electrical engineer
Contractor
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Reinforced concrete is concrete strengthened with steel bars or reinforcements
Concrete is a mix of cement, sand, aggregate and water. High compression strength but lower in tension.
Steel reinforcement has high tension strength
Concrete
Higher compressive
strength
Steel
Higher tensile
strength
Reinforced concrete
The Eurocode Family (58 all together)
EN 1990 Eurocode Basis of structural design
EN 1991 Eurocode 1 Actions on structures
EN 1992 Eurocode 2 Design of concrete structures
EN 1993 Eurocode 3 Design of steel structures
EN 1994 Eurocode 4 Design of composite steel and concrete structures
EN 1995 Eurocode 5 Design of timber structures
EN 1996 Eurocode 6 Design of masonry structures
EN 1997 Eurocode 7 Geotechnical design
EN 1998 Eurocode 8 Design of structures for earthquake resistance
EN 1999 Eurocode 9 Design of aluminium alloy structures
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EUROCODE 2 : DESIGN OF CONCRETE STRUCTURES
EN 1992-1-1 General rules and rules for buildings
EN 1992-1-2 General rules – Structural fire design
EN 1992-2 Concrete bridges – design and detailing rules
EN 1992-3 Liquid retaining and containment structures
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Eurocodes Title Superseded standards
EN 1990 Basis of structural design BS 8110: Part 1- Section 2
EN 1991-1-1 Densities, self-weight and imposed loads
BS 6399: Part1 and BS 648
EN 1991-1-2 Action on structures exposed to fire
-
EN 1991-1-3 Snow loads BS 6399: Part 2
EN 1991-1-4 Wind loads BS 6399: Part 3
EN 1991-1-5 Thermal actions -
EN 1991-1-6 Actions during execution -
EN 1991-1-7 Accidental actions -
Eurocodes Title Superseded standards
EN 1991-2 Traffic loads on bridges BD 37/88
EN 1991-3 Actions induced by crane and machinery
-
EN 1991-4 Silos and tanks -
EN 1992-1-1 General rules for buildings BS 8110: Parts 1, 2 and 3
EN 1992-1-2 Fire resistance of concrete structures
BS 8110: Part 1 Table 3.2 BS 8110: Part 2 Sect. 4
EN 1992-2 Bridges BS 5400: Part 4
EN 1992-3 Liquid-retaining and containment structures
BS 8007
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Eurocode British Standard
Action Force or imposed displacement
Verification Check
Resistance Capacity
Execution Construction
Permanent action Dead load
Variable action Live load or imposed load
Isostatic Primary
Can be downloaded at: http://web.utm.my/psz/
MAIN CODE
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Can be downloaded at: http://web.utm.my/psz/
NATIONAL ANNEX
Logi Rawatan Air Jambatan
2.3 Design working life
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Ultimate Limit State (ULS)
A condition where failure of an element or the whole structure e.g. collapse, overturning, buckling
Serviceability Limit State (SLS)
A condition where the structure is not suitable or comfortable for living e.g. cracking and large deflection
Section 3 : Principle of Limit States Design (EN 1990) 3.2 Design Situations Persistent: Design situation during a period of the same order as he design working life of the structure. Represents normal use Transient: Design situation during a period much shorter than the design working life of structure, e.g. during execution or repair Accidental: Design situation involving exceptional conditions for structure, e.g. Fire, explosion, impact etc Seismic: Design situation involving exceptional conditions for structure during seismic event.
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Design strength, Xd = Characteristics strength, Xk / Partial Safety Factor, m
Design Situations c for Concrete s for Reinforcing Steel
Persistant & Transient 1.5 1.15
Accidental 1.2 1.0
Material Characteristics Strength
1.64s
Mean strength, f
Strength
Pro
babili
ty d
ensity
Area = 0.05
m
Characteristics strength
= Mean strength – 1.64s
Example:
To get concrete with characteristics strength of 30 N/mm2 and s = 5 N/mm2, the mean strength will require 38.2 N/mm2
Ch
arac
teri
stic
s st
ren
gth
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fck is the concrete compressive cylinder strength at 28 days. Strength value or grade concrete is usually 25, 30, 40 and 50 N/mm2
Actual Test Curve
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Design Curve
fck = 0.85fck = 0.567fck
c 1.5
Concrete strength class
Characteristics cylinder strength, fck
(N/mm2)
Characteristics cube strength, fck
(N/mm2)
Modulus of Elasticity, Ecm
(kN/mm2)
C20/25 20 25 30
C25/30 25 30 31
C30/37 30 37 33
C35/45 35 45 34
C40/50 40 50 35
C45/55 45 55 36
C50/60 50 60 37
C55/67 55 67 38
C60/75 60 75 39
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fyk is the yield strength of the steel
High strength steel (H); fyk = 500 N/mm2
Mild strength steel (R); fyk = 250 N/mm2
Steel fabric (BRC); fyk = 485 N/mm2
Actual Test Curve
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Design Curve
fyk = fyk = 0.87fyk
s 1.15
Ribbed high yield bars may be classified as:
Class A: which is normally associated with small diameter ( 12 mm) cold worked bars used in mesh and fabric
Class B: which is most commonly used for reinforcingg bars
Class C: high ductility which may be used in earthquake design or similar situations
e.g. HA, HB, HC
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Section 4 : Basic variables 4.1 Actions and environmental influences 4.1.1 Classification of actions (1)P Actions shall be classified by their variations in time as follows: Permanent actions (G): e.g. Self-weight of structures, fixed equipment and road surfacing, and indirect actions caused by shrinkage and uneven settlements; Variable actions (Q): e.g. Imposed loads on building floors, beams and roofs, wind actions or snow loads; Accidental action (A): e.g. Explosion, or impact from vehicles.
For each variable actions there are four representative values: 1. Characteristic Value, (Qk) – An upper value with an intended
probability of not being exceeded or a lower value with an intended probability of being achieved, during some specific reference period
2. Combination Value, (oQk) – Value intended to take account of a reduced probability of the simultaneous occurrence of two or more variable actions.
3. Frequent Value, (1Qk) – value such that it should be exceeded only for a short period of time and is used primarily for the serviceability limit states and also accidental limit state.
4. Quasi-permanent Value, (2Qk) – value may be exceeded for a considerable period of time; alternatively it may be considered as an average loading over time. It is used for a long term effects at the SLS and also accidental and seismic ULS.
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Recommended Values of Factors for Buildings
Action 0 1 2
Imposed loads in buildings (see EN 1991-1-1)
Category A: domestic, residential areas 0.7 0.5 0.3
Category B: office areas 0.7 0.5 0.3
Category C: congregation areas 0.7 0.7 0.6
Category D: shopping areas 0.7 0.7 0.6
Category E: storage areas 1.0 0.9 0.8
Category F: traffic area, vehicle weight < 30 kN 0.7 0.7 0.6
Category G: traffic area, 30 kN < vehicle weight < 160 kN 0.7 0.5 0.3
Category H: roof (see EN 1991-1-1: Cl. 3.3.2) 0.7 0 0
Wind loads on buildings (see EN 1991-1-4) 0.5 0.7 0.7
Temperature (non-fire) in buildings (see EN 1991-1-5) 0.6 0.7 0.7
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Combination
Expression
Permanent actions Leading
variable
actions
Accompanying variable
actions
Unfavourable Favourable Main (if any) Others
Exp. (6.10) Gj,sup Gkj,sup Gj,inf Gk,j,inf Q,1Qk,1 Q,i 0,i Qk,i
Exp. (6.10a) Gj,sup Gkj,sup Gj,inf Gk,j,inf Q,1 0,1 Qk,1 Q,i 0,i Qk,i
Exp. (6.10b) Gj,sup Gkj,sup Gj,inf Gk,j,inf Q,1Qk,1 Q,i 0,i Qk,i
Notes: 1. The choice between 6.10, or 6.10a and 6.10b will be in the National annex. 2. The and values may be set by the National annex. The following values for and are
recommended when using 6.10, 6.10a and 6.10b. Gj,sup = 1.35, Gj,inf = 1. 0, Q,1 = 1.50 where Unfavourable (0 where favourable) Q,i = 1.50 where Unfavourable (0 where favourable), = 0.85
Table A1.2(B) : Design values of actions – Ultimate limit states for persistent and transient design situation
Combination Expression
Permanent actions Leading variable actions
Accompanying variable actions
Unfavourable Favourable Main (if any) Others
Exp. (6.10) 1.35Gk 1.0Gk 1.5Qk 1.50,iQk,i
Exp. (6.10a) 1.35Gk 1.0Gk 1.50,1Qk 1.50,iQk,i
Exp. (6.10b) 0.925x1.35Gk 1.0Gk 1.5Qk 1.50,iQk,i
Note: 1. Design for either Exp.(6.10) or the less favourable of Exp. (6.10a) and (6.10b) 2. The terms favorable and unfavorable refer to the effect of the action on the design situation under consideration.
For example, if a beam, continuous over several spans, is to be designed for largest sagging bending moment it will have to sustain any action that has the effect of increasing the bending moment will be considered unfavorable whilst any action that reduces the bending moment will be considered to be favourable.
Design values of actions, ultimate limit state-persistent and transient design situations
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Combination
Permanent actions Variable actions
Example of use
Unfavourable Favourable Leading Others
Characteristic 1.0Gk 1.0Gk Qk,1 0,iQk,i
Frequent 1.0Gk 1.0Gk 1,1Qk,1 2,1Qk,i
Cracking –prestressed
concrete
Quasi-permanent
1.0Gk 1.0Gk 2,1Qk,1 2,1Qk,i Deflection
Design values of actions, serviceability limit states
P P
P P
d
b cc
st
fcc
fst 0.87fyk fyd = 0.87fyk
fcd = 0.567fck
Fst
0.567fck
x
s =
0.8x
N. A
Strain diagram
Stress diagram at service
Stress diagram at ultimate
EC2 stress diagram at ultimate
Fcc
z
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cc / x = st/(d – x) x = d/ [1 + (st / cc)]
At failure at ultimate limit state, steel and concrete reached maximum stress and strain; Concrete strain, cc = cu2 = 0.0035 for concrete class C50/60
Steel strain, st = Stress / Elastic Modulus
= (fyk / m) / Es
= (fyk / 1.15) / 200 103 = (4.35 10-6)fy
For high tensile steel (T), fy = 500 N/mm2
st = 4.35 10-6 (500) = 0.00218
and x = d/ [1 + (0.00218 / 0.0035)] = 0.617d
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