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National Highways Authority of India Consultancy Services for Feasibility study and Detailed Project Report or 416 Laning of Karur- Madurai section of NH-7 from Km 30518 to 42616

in the State of Tamil Nadu (Consultancy Package C-ll Alll)

VOLUME III : MATERIAL REPORT

January 2005

BCEOM -77- -U7 ;-

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a E B . ~ P E P A I I o H RE9E

SUMMARY

Sr. No Particular

Volume 1 Concession Agreement ,Schedules and SPV Details for DS Toll Road Limited

Volume 2 RFP, Response to Queries and Addendum for DS Toll Road Limited

Volume 3 DPR for DS Toll Road Limited

Table of Contents

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TABLE OF CONTENTS

CHAPTER - I S. No Description

1.0 MATERIAL INVESTIGATIONS

1 .I Introduction

1.2 Project Description

1.3 Objective Of Material lnvestigation

1.3.1 lnvestigation for Embankment and Sub grade

1.3.2 Pavement Materials

1.3.3 Stone Aggregate

1.3.4 Sand

1.3.5 Cement, Steel and Bitumen

CHAPTER - II

2.0 SUBGRADE INVESTIGATIONS

2.1 Introduction

2.2 Project Description

2.3 Sub grade Soil Investigations

2.3.1 Methodology

2.3.2 Results of lnvestigations

2.3.3 Field Tests on Existing Alignment

2.4 Recommendations

Page No.

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Final Detailed Project Report Table of Contents i Contract Package: - NS 81 (TN) I

Volume Ill: ate rial Report

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LlST OF FIGURES

Fig. No Description Page No.

Table No

Project road and & location of various quarries and borrow areas

Soil Classification

Plasticity lndex

MDD of Borrow Area Samples

CBR of Borrow Area Samples

Soil Classification

Plasticity lndex

FDD & MDD

FMC & OMC

Soaked CBR at 97% MDD

LlST OF TABLES

Description

Test Results of Borrow Area Samples

Test Results of Gravel Samples

Test Results of Aggregates Samples

Test Results of Sand Quany Samples'

Borrow Areas for Embankment I Sub grade

Summary of Test Results

Results of CBR & SNSG from DCP Tests

Summary of Test Results

Summary of Test Results

Page No.

Contract package: - NS 81 (TN) Volume Ill: Material Report

-v

Chapter 1 : Material Investigations

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1.0 REPORT ON MATERIAL INVESTIGATIONS

1.1 INTRODUCTION

The Ministry of Road Transport and Highways (MoRT&H), Govt. of lndia has taken up the development of various National Highway Corridors where the traffic intensity has increased significantly thereby necessitating capacity augmentation for safe and efficient movement of traffic. This Project is a part of North - South corridor connecting Srinagar in J&K State to Kanyakumari in Tamil Nadu. National Highways Authority of lndia (NHAI) has been entrusted to implement the development projects for these corridors. The work of conducting Feasibility Studies and Preparation of Detailed Project Report for Four 1 Six laning from Karur (Km 305.800) to Madurai (Km. 426.660), a section of NH 7 has been entrusted to the Joint Venture of BCEOM - Aarvee Associates.

For the convenience in construction, the present project corridor has been divided into three packages. They are:

Package NS-80 (TN): Km 305.800 to Km 345.000 Package NS-81 (TN): Krn 345.000 to Km 381.200 Package NS-82 (TN): Km 381.200 to Km 426.660

In this present chapter, the data pertaining to the Construction package: NS-81 (TN) is presented.

1.2 PROJECT DESCRIPTION

The road section from Km 345.000 to Km 381.200 of NH-7 (Package NS81 (TN)) is taken up for conducting detailed engineering studies for rehabilitation and up-gradation of existing 2 lane to 4 lane divided carriage way highway with improved traffic capacity. Suitable construction materials (such as embankment material, sub-grade material, Granular sub base material, metal quarries and Aggregate crushers) investigations form an essential part of studies conducted for identification of potential sources with minimum lead and easy approach to the construction site. The study involves assessing the requisite quantity available in respect of estimated quantity.

The investigation entails carrying out the visual locations of Borrow areas, locations of quarries etc. with approachable minimum lead, collection of samples, laboratory testing for assessing their quality, and suitability, and assessment of their quantity available for construction purposes.

The investigation and testing of materials is carried out in accordance with the provisions of TOR clause 4.1'1.5. A mass haul diagram is also prepared and enclosed indicating locations of selected Borrow areas, quarries etc. haulage routs with minimum lead approximate quantity available against the requirement and the ownership of the Borrow areaslquarries etc. The following sections discuss about the details of samples collection, laboratory tests carried out

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1.3 OBJECTIVE OF MATERIAL INVESTIGATIONS

Basic objective of material investigations is to identify the potential sources of construction materials along the project stretch, to yield adequate quantity of materials which are suitable for various pavement layers viz. embankment, sub grade, sub base, base, etc.

Suitable sources have been identified along the project stretch by local enquiry. However, consultants have carried out tests on selected sources to find their suitability for use. Sufficient number of quarries has been identified to verify availability of materials within economical leads.

The information on the materials sources was summarized with the following objectives:

ldentification of source locations indicating places and the status of quarries whether in operation or new sources. Identification of requirements for road pavements, shoulder works, cross drainage and other works.

Material specification and characteristics. Testing and evaluation of materials for use in works.

Consultants have identified a number of quarries for stone, sand, gravel and borrow areas for earth. More borrow areas are available along the roadside. The samples were tested in the laboratory to evaluate their suitability for road construction. A sketch showing the project road and location of various quarries and borrow areas is given Figure 1 .I.

1.3.1 Investigation for Embankment and Subgrade

Material was collected from the borrow areas and tests were conducted to determine the following parameters:

Grain size analysis Atterberg's limits Compaction characteristics

Strength characteristics

Table 1.1 presents details of location of borrow areas for embankment and subgrade. The analysis brings out the following

Soils are predominantly GC (60%) and SC(40%) Plasticity index ranges from 11% to 21 %

Maximum dry density is ranges from 2.05 gmlcc to 2.24 gmlcc

CBR was found to be ranging between 21 % to 41 %

Figure 1.2 to Figure 1.5 shows the location wise variation of Plasticity Index, Maximum dry density and CBR respectively. The summary of test results of borrow area samples furnished in Table 1.1 and Gravel samples in Table 1.2. The details of quarry and borrow locations are given in Table 1.5.

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LEGEND

PROJECT ROAD - MAJOR ROADS RIVER/STREAM NH/SH HIGHWAYS- OTHER ROADS RAILWAY LINE - AGGREGATE QUARRY SAND QUARRY

GRAVEL QUARRY A BORROW QUARRY@ I

-.

M Figure 1.1. The project road and location of various quarries and borrow areas

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Soil Classffication

GC 80%

Fig. 1.2 Soil Classification

Fia 1.3 Plasticitv lndex

Plastlclty lndex

Fia I -4 MDD of Borrow Area Sarnales

25 *

20 -

15 -.

t 10 -

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Chapter - 1: Material Irivestigations 4of11

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CBR (%)

45

40

35

- 30 5 25 $ 20 0

15

10

5

0 34412 35316 37212 37616 37916

Location of Borrow Area

Fig 1.5 CBR of Borrow Area Samples

1.3.2 Pavement materials

The pavement has been designed to comprise the following materials:

SurfaceMlearing course - Bituminous Concrete Base Course - Dense Bituminous macadam I Wet Mix Macadam Sub-base Course - Granular sub-base

For the above components, the basic materials available from natural 1 quarry sources are shown in Table 1.3 and analysis brings out the following

I .3.3 Stone Aggregate

Samples have been collected from the existing quarries and crushers to find their suitability for use in the cement concrete, sub base, base and wearing 6ourses.

The aggregates have been subjected to the following tests:

Impact value Specific gravity and water absorption

Stripping value Soundness

In the primary investigations, the aggregates seem to be having a stripping value of more than 5%. It may be required to add anti stripping agents to bitumen during construction of asphalt courses. The test results are furnished in Table 1.3.

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1.3.4 Sand

Sand has been collected from three quarries and all the quarries satisfy requirements of Zone - II sand, which is ideal for reinforced concrete. But, there is a recent order that sand can be sold only through PWD outlets. Quality control with this setup may be difficult. Hence, it is suggested to manufacture "crusher sand " by installing additional machinery along with stone crusher. The test results are furnished in Table 1.4.

1.3.5 Cement. Steel and Bitumen

Cement, bitumen, steel etc are the manufactured materials. Bitumen is produced indigenously in lndia and is generally supplied from the nearest oil refinery. Regular supply of bitumen can be satisfactorily met by advance agreements.

Cement conforming to BIS specifications can be procured directly form factories or can be purchased from dealers of the factories in all the major towns along the project road. The reinforcement steel both CRS and ordinary Tor steel of different grades conforming to BIS specifications is available. Hence there is no difficulty in respect of its availability in this project.

The nearest sources are:

Bitumen Madras Refinery / Cochin refinery Cement India Cements, Chennai. Steel Rashtriya lspat Nigam Limited O/isakhapatnam Steel Plant)

Final Detailed Project Report Chapter - I: 6 of 11 Contract Package - NS81 (TN) Volume Ill: Material Report

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Table 1.1 Test Results of Borrow Area Samples

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B6

2.245

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R

L

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VWge Name

Medamhpani

Dindigul Outer

&patti

Ly (Km.)

0.2

0.2

5.8

Quarry Loutian

Near Mcdamkampani village

Near Dindigul Stadium

At Dindigul- Cairnbatore road ( NH-209)

N e a M ~oaetion or

Pmjcct Road (Km.)

35316

37212

376/6

Sive Analyds (Cum. % Pawlag)

2 6 mm

100

95

IW

Anerberg'l Limb

sou Type

SC

OC

sc

LL (%I

27

38

32

19 mm

99

90

97

236 mm

61

38

61

PL (%)

14

17

15

9.5 i n

97

74

93

PI (%)

13

21

17

Proctor Tmt (He8vy)

' mm

72

45

74

mm

48

33

53

lw=

2.08

2.18

2.05

CBR Value (*A) ,

Soaked

OMC %

9.80

L0.12

9.30

st MDD

21

38

23

OAZ5 mm

37

29

42

zzT 11.75

12.3

11.12

0.075 mm

24

23

31

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final Detailed Project Report Contract Package - NS 81 (TN) Volume Ill: Material Report Material

Chapter 2 : Subgrade Investigations

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2.0 REPORT ON SUBGRADE INVESTIGATIONS

2.1 INTRODUCTION

The Ministry of Road Transport and Highways (MoRT&H), Govt. of lndia has taken up the development of various National Highway Corridors where the traffic intensity has increased significantly thereby necessitating capacity augmentation for safe and efficient movement of traffic. This Project is a part of North - South corridor connecting Srinagar in J&K State to Kanyakumari in Tamil Nadu. National Highways Authority of lndia (NHAI) has been entrusted to implement the development projects for these corridors. The work of conducting Feasibility Studies and Preparation of Detailed Project Report for Four I Six laning from Karur (Km 305.800) to Madurai (Km. 426.660), a section of NH 7 has been entrusted to the Joint Venture of BCEOM - Aarvee Associates.

For the convenience in construction, the present project corridor has been divided into three packages. They are:

Package NS-80 (TN): Km 305.800 to Km 345.000 Package NS-81 (TN): Km 345.000 to Km 381.200 Package NS-82 (TN): Km 381.200 to Km 426.660

In this chapter, the data pertaining to the Construction package: NS-81 (TN) is presented.

2.2 PROJECT DESCRIPTION

The road section from Krn 345.000 to Km 381.200 of NH-7 (Package NS81 (TN)) is taken up for conducting detailed engineering studies for rehabilitation and up-gradation of existing 2 lane to 4 lane divided carriage way highway with improved traffic capacity. Soils and material investigation for a road project is an essential requirement to assess real scenario for design and construction. During design stage, the road pavement, embankment, and other structures, the existing soils and materials inventory is needed for their characteristics, availability in right quality and quantity for constructions at reasonable cost. The investigations covered all relevant aspects.

All relevant information such as geological maps data published by various authorities regarding soil profile, ground water quality etc., have been studied to the extent possible. Subgrade investigations along the alignment of the project was essentially directed towards collecting all the data about the existing pavement, subgrade etc., necessary for strengthening the existing pavement for widening and paved shoulders and for new bypass alignments.

The investigation and testing of materials is carried out in accordance with the provisions of TOR clause 4.1 1.3.3.

2.3 SUBGRADE SOIL INVESTIGATIONS

Subgrade investigations along the alignment of the project was essentially directed towards collecting all the data about the existing pavement, subgrade etc., necessary for strengthening the existing pavement for widening and paved shoulders and for new bypass slim, . . .. ,, ". ,. ..

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2.3.1 Methodology

All relevant information such as geological maps data published by various authorities regarding soil profile, ground water quality etc and data available with PWD (NH) have been studied to the extent possible. In addition fresh investigations were carried out by cutting trial pits in the following manner.

Large test pits (1.0m x 1.0m) were excavated at the pavement - shoulder interface to a depth of 1 m, Minimum three pits were dug for each homogeneous road segment or change of soil as per TOR and staggered left/right for carrying out the following activities.

P Measuring and logging the thickness of various pavement layers. P Conducting field (in-situ) density test using sand replacement method as per 1832720 part-28 P Field moisture content P Conducting DCP Test (TRL Method) down to a depth of 1.5m below subgrade level. P Collecting samples of subgrade (approx. 50Kg) for following laboratory tests

3 Atterberg limits As per 18:2720 3 Grain size analysis As per 1832720 s Maximum laboratory As per 1832720

Dry density (heavy compaction)

3 Optimum Moisture content As per 1S:2720 2 CBR (4 days soaked) at AASHTO TI 93

three energy levels * Free swell index As per lS:2720

P Collecting Auger samples at different depths for Laboratory tests for soil classification

Small pits (0.7m x 0.7m) were dug upto the subgrade level at the pavement - shoulder interface staggered leftlright in between the large pits at every 1 km interval. The following activities were carried out

P Measuring and logging the thickness of various pavement layers P Collecting samples of subgrade for following laboratory tests

3 Atterberg limits,

s Grain size analysis 3 Natural moisture content 3 Free swell index

New Alignment: Pits on natural ground adjoining the existing pavement to assess the soil strength for new carriageway1 proposed bypass alignments at every 5Km interval and the following activities were carried out.

Collecting bulk samples (approx. 50Kg) for following laboratory test.

3 Atterberg Limits 3 Grain size analysis 3 Maximum Laboratory dry density (heavy compaction) s Optimum moisture content

3 CBR (4 days soaked) at three energy levels ,--;:-, .N ', ,.,,\ / ". .---a, , n y ".

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=> Free swell index > Driving auger down to 1.5m below the natural ground or till hard strata is encountered, k collecting I Kg sample at 1 .Om and 1.5m depth for soil classification k Recording water table, If encountered in the bore.

2.3.2 Results of Investigations

The results of field and laboratory investigations have been compiled in the form of tables and are given in the Appendix, at the end of this chapter.

Table 2.1 Test results at Subgrade level at every Ikm interval from small pits

Table 2.2 DCP-CBR value at Sub-grade and below sub-grade level

Table 2.3 Test results at Subgrade and below sub-grade level from large pits

Table 2.4 Test results of natural ground

2.3.3 Field Tests on Existing Alignment

2.3.3.1 Existing Sub-grade

The existing sub-grade soils have been investigated for moisture content, density, DCP-CBR etc. The test was done staggered at the junction of shoulder and carriageway through test pit dug up to the formation level as per standard procedure.

2.3.3.2 Dynamic Cone penetration Test: (TRRL Method)

Dynamic Cone Penetration test according to TRL method was conducted to assess the in-situ CBR at and below subgrade level. The test was conducted at large pits along the existing pavement edge (300 mm from the edge of the carriageway) of the road. TRRCs DCP apparatus consists of a hardened steel cone (60°cone) 20 mm in diameter, which is driven by a weight of 8 Kg with a drop height of 575 mm. The CBR value was calculated for different soil layers encountered from the graph of penetration versus number of blows. Slope changes of penetration versus number of blows graph indicates interface of two soil layers. From this graph, layer thickness and respective slopes (penetration 1 blow) have been calculated.

DCP-CBR value have been calculated using the following formula (TRL overseas RodeNote-8 using 60" cone)

Loglo CBR = 2.48 - 1 .057*loglo (rnrnlblow)

The above DCP-CBR value was converted to an overall equivalent DCP - CBR value using the following Japanese formula.

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Overall CBR = [(C(Layer thickness) x (DCP - CBR)'") I @(Layer thickness)]'

Table 2.2, Appendix gives the data on the overall CBR. Maximum, minimum and average values of DCP-CBR value have been found to be 55.1, 38.2 and 49.3 respectively.

2.3.3.3 Laboratory test results o f the existing sub-grade

Laboratory test results obtained from small pits have been grouped along with results of large pits and analyzed. The soil samples have been primarily classified on the basis of Bureau of Indian Standards (BIS) which is based on the unified soil classification System (UCS). Density-moisture relation, CBR (soaked) swell at 10, 30 and 65 blows, were determined. Comprehensive results of laboratory tests on subgrade Fig 2.1 Soil Classification

samples of the existing pavement are summarized in Table 2.1 & 2.3 in Appendix. subgrade soil is mostly sand, sandy clay and some gravel material, with low plasticity. The soil is mostly classified as SM I SC group according to the UCS System. Soil profiles along the alignment have been given in figure 2.6, Appendix.

The

Grain size analysis: In the entire section soil, the 75 micron passing material is 30% (average value) which ranges from 12.5% to 81.9%.

Soil Classification

SM 3%

SC 67%

Plasticity lndex

20-30 8% NP

%

1 0-2 10-20

51% 0-1 0 8%. b

Fig 2.2 Plasticity lndex

Atterberg's Limits: The mean Liquid limit and Plastic limit values are found to be 27% and 16% respectively. The average value of plasticity index of the soil is found to be 14%. About 8% of soil samples have a PI value in the range of 0-lo%, 51% of samples in the range of 10-20%, 8% of samples in the range of 20-30% and 33% of soil samples are non-plastic in nature, and is given in the figure 2.2. Moisture content vs. Dry Density relationship (Heavy compaction) is given in the figure 2.4. Soil samples obtained from trial pits have been compacted in the laboratory at various moisture contents to derive a dry density versus moisture content relationship. The method of heavy compaction in accordance with IS: 2720 (Part8) has been adopted, given in figure 2.3.

It shows Subgrade soil having maximum dry density (MDD) ranging from 1.86 grnlcc to 2.18 gmlcc. The optimum moisture content (OMC) varies from 8.0% to 13.8% showing an average of 10.64%.

California Bearing Ratio (CBR) tests were carried out on as per standard procedures. At OMC, the soil samples were

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corresponding to 10 blows, 30 blows and 65 blows as per 18:2720 (Part8). The samples were tested after immersion in water and soaking for four days. The amount of swell, soaked moisture and density were determined for the samples. For the same samples CBR at FDD, 95% of MDD, 97% of MDD and at MDD has been interpolated from the results at different levels of compaction.

Comprehensive results of laboratory investigations are tabulated in Table 2.3 of Appendix. The soaked CBR at MDD ranges from 9.57% to 21% and

FDD 8 MDD

-c- MDO (%)

0 0

8 8 0 0 8 8 8 8 8 % K % ? g ; g P X 2 $ % , , - " 2

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Fig 2.3 FDD & MDD

the soaked CBR at FDD ranges from 7.59% to 16.26%. Figure 2.5 presents the results of soaked CBR compacted at 97% MDD.

The field dry density and moisture content of the subgrade soil has been measured at every large pit and the results are illustrated in Table 2.3 of Appendix. It shows a range of FDD from 16.70kNl m3 having an average value of 20.7kNI m3. The field moisture content (FMC) varies from 2% to 13.5% having an average value of 6.31%. The average ratio of FMC and OMC is 0.593 while the ratio of FDD and MDD is 0.93.

FMC & OMC CI

C W 15 - C

O 10 0- 0s L-

=I 5 C)

VI .- 0 0 = 0 0 0 0 0 0 0 0

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 + + + + + + + + m c v m - m - m - W m m m c D b b C o C r ) C C ) ~ C C ) O C r ) C C ) C C )

C hainage

Fig 2.4 FMC & OMC

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Investigation of natural ground abutting the existing carriageway and along proposed alignment of bypasses was done through test pit and auger samples collected for Laboratory tests.

Fig 2.5 CBR (%) at 97% MDD

CBR (%)

25 -----

Comprehensive results of laboratory tests are presented in Table 2.4 of Appendix.

Grain size analysis : Results of Grain size indicates an average value of 75 micron down material is 30% (Range 12.5 % to 81.9%) Atterberg's Limits: The mean Liquid limit and Plastic limit values are found to be 27% and 16% respectively. The average value of plasticity index of the soil is found to be 14%.

-1 - 20 - c 1 5 - .

g I 0 0 5 --

Moisture content vs. Dry Density relationship (Heavy compaction) 3 Average Maximum dry density (MDD) of the natural ground is 2.00gIcc. The optimum

moisture wntent (OMC) varies from 8.0% to 13.8% showing an average of 10.6%. CBR Test: Laboratory CBR on the test pit sample from natural ground at MDD has been found to be 14.4% (average value) with a range of 9.6% to 21 %. Auger Samples: Auger samples were collected at three depth 50cm, Im, 1.5m for natural moisture wntent. The soil samples from different depths were collected at each site and representative test samples were prepared for analysis.

0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 + + + + + + + + m ~ w ~ ( ~ ~ w ~ * L D L D ( D ( D l . l . m m m m m m m m m

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2.3.3.4 Interpretation of Test Results

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Majority of the alignment soil is mostly sand, sandy clay and some gravel material, with low plasticity. The soil is mostly classified as SM or SC group according to UCS system.

Existing Subgrade

In-situ average DCP-CBR value is 49.3% with large variation (Range: 38.2% to 55.1%) which is more than Laboratory CBR 14.4% (Range: 9.6% to 21%). This indicates the densification of sub-grade has occurred over a period of time.

Average Optimum Moisture Content (OMC) is 10.6% where as Natural Moisture Content (NMC) is about 6.3%. Therefore the mean NMC is 57% less than

New Sub-grade1Natural ground

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Majority of the natural soil abutting existing alignment is predominantly sandy claylsandy silt (SC or SM group) and average Laboratory CBR 15.17% (Range 10% to 22%). Average Optimum Moisture Content (OMC) is 12.18% where as Natural Moisture Content (NMC) at a depth of 0.501~1, l m and 2m below ground level was collected and presented in Table 2.4, Appendix.

2.4 RECOMMENDATIONS

Geotechnical Investigations including subsurface drilling at the locations of piers and abutments of the various bridges and flyoversIRoBs, insitu testing and laboratory testing were carried out during April 2004 to June 2004 through a geotechnical consultant.

The subsoil investigation work was carried conforming to the requirements of the relevant IS and IRC codes and specifications. The boreholes were advanced using rotary type drilling, SPT values were recorded in the soil formation at on interval of 1.5m generally. Where rock formations were met with, cores were recovered using double tube core barrel. Since formation was sandy soil followed by weathered rock or rock, all through the alignment, it was found possible to adopt open foundations. The depth of foundation was mostly in the range of 2 to 3m and a safe bearing capacity of 30-45 tlm2 was adopted. In a few cases foundation depth was deeper. In case of lightly loaded structures, foundation were located on sandy layers and allowable bearing capacity of 15 to 25 tlm2 was adopted.

Basic input for the design of pavements is the soaked CBR value compacted at 97% MDD. Considering this parameter, and the type of existing soils available, a soaked CBR value of 10% has been adopted uniformly for the design of existing and new pavement.

In order to evaluate the stability of high embankments in the approaches to bridge and other structures, two bore holes were drilled in each of the approaches as well as the strength properties of fill soils were evaluated. The sub-soils in the stretch are materials having high shear strength as also the fill materials. The high embankments are safe with 1 :2 side slopes.

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Table 2.1 : Summary of Test Results Laboratory test results of Subgrade soil samples at small pits

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Volume Ill: Material Report h

Chapter- 2 : Subgrade Investigation

'1\

Depth (m) Sieve Analysis (CUM. % PassiNA) Location

Atterberg Limits

from top of 5 +, -

a $ 3 0

SM

53 mm

100

LL (%)

25

/Chainage (Kmm)

346+000

- 0 - c 5 1 2 3 '

8.9

26.5 mm

100

PL (%)

N.P

the pavement

0.65

Pi (%)

75 mrn

100

9.5 rnm

100

4.75 mm

100

2.36 mm

100

0.425 mm

87.3

0.075 mm

22

4 /6 Laning of Karur - Madmi Section Of NH-7 ConsuLncyServioesforFessibrMystudyand~~ofDPR rd

m Final Detailed Prcjecl Report contraa Package - NS81 (TN) Volume Ill: Material Report Chapter - 2 : Subgrade Investigation

h

h

Table 2.2 : Results of CBR 8SNSG from DCP Tests

S. No.

1

Test location

(km)

349+000

Layer 1 .

149

Layer2 No. of blows

15 193

DCP- CBR

26.7

Layer3 No. Of

blows

35

Thickness

33

Overall CBR DCP- CBR

49.7

Japanese

48.6

No.of blows

30

SNSG

2.07

DCP- CBR

273.1

Final Detailed Pmject Report Contract Package - NS81 ( 'N ) Volume Ill: Material Report

Chapter - 2 : subgrade Inves@ation

- p ~ ~ -

Final Detailed Project Report Contract Package - NS81 (TN) Volume Ill: Material Repolt Chapter - 2 : Subgrade Investigations