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GEOTECHNICAL INVESTIGATION

REPORT

PROJECT

REPORT ON GEOTECHNICAL INVESTIGATION WORK FOR PROPOSED 33 KV GRID STATION

AT NAAZ CINEMA (D) SRD

SUBMITTED BY

RAO ENGINEERING ENTERPRISES GEOTECHNICAL CONSULTANTS & LAND SURVEYORS

91-D-3, STREET NO.1, EAST MOTI BAGH , OLD ROHTAK ROAD, DELHI-110007. PHONES :011-23698806, Mob. 09310502435, 9310402435 , 9811108174, TeleFax-23691434

e-mail : [email protected] , [email protected]

PROJECT : REPORT ON GEOTECHNICAL INVESTIGATION WORK FOR

PROPOSED 33 KV GRID STATION AT NAAZ CINEMA(D)SRD. CLIENT : BSES YAMUNA POWER LIMITED SHAKTI KIRAN BUILDING, KARKARDOOMA, DELHI. REPORT NO. : 5203 DATE : 26.02.2013

RAO ENGINEERING ENTERPRISES - - - GEOTECHNICAL REPORT

PROJECT : REPORT ON GEOTECHNICAL INVESTIGATION WORK FOR PROPOSED 33 KV GRID STATION AT NAAZ CINEMA(D) SRD

C O N T E N T S

PAGE NO.

1.0 INTRODUCTION 1 1.1 PROJECT DESCRIPTION 1 1.2 AIM OF SOIL INVESTIGATION 1-2 1.3 SCOPE OF WORK 2 2.0 INVESTIGATIONS CONDUCTED 3 2.1 INSITU TESTS 3 2.1.1 BOREHOLES 3 2.1.1.1 WATER TABLE 3 2.1.1.2 FIELD TEST RESULTS 4 2.2 LABORATORY TESTS AND RESULTS 5 3.0 OBSERVATIONS 6 4.0 DISCUSSIONS 6 4.1 TYPE & DEPTH OF FOUNDATION 7 4.2 ALLOWABLE BEARING PRESSURE 7 5.0 RECOMMENDATIONS 8 6.0 ELECTRICAL RESISTIVITY TEST RESULTS 8 7.0 CHEMICAL ATTACK 8-9 8.0 CLOSURE 9 ------ FIGURES 1-9

*****************************

RAO ENGINEERING ENTERPRISES - GEOTECHNICAL REPORT - PAGE 1

1.0 INTRODUCTION

1.1 PROJECT DESCRIPTION

This soil investigation work , whose results are being presented herewith , has been carried out for proposed 33 KV Grid Station at Naaz Cinema (D) SRD.The proposed building may consists of Ground+2-3 storied. A layout plan showing the locations of our field investigation is illustrated in our report.

1.2 AIM OF SOIL INVESTIGATION Soil investigation has been conducted at the site in order to evaluate the parameters required for design of foundations. These parameters are :

(a) Type of foundation on which the

proposed super structure will be supported.

(b) Depth of foundation , and (c) Allowable bearing pressure at the

founding level.

RAO ENGINEERING ENTERPRISES -- GEOTECHNICAL REPORT - PAGE 2

To evaluate these parameters , following engineering properties of the sub - Rock strata have been studied :

(a) Core recoveries and Rock quality designation (RQD) for different core runs.

(b) Properties like Moisture content, Bulk density ,

Water absorption, Porosity, Void ratio, Crushing strength, Point load etc; which have been determined in the laboratory by conducting testing of cores obtained from rock drilling.

1.3 SCOPE OF WORK

The stipulated scope of work comprised of the following : 1. Mobilization of equipment and personnel to the

site and back. 2. Sinking 3 boreholes through soil/rock strata to

6.0 – 9.40m depth, observing ground water table levels, conducting required field and laboratory tests and their analysis.

3. Preparation and submission of technical report in triplicate.

RAO ENGINEERING ENTERPRISES -- GEOTECHNICAL REPORT - - PAGE 3 2.0 INVESTIGATIONS CONDUCTED 2.1 INSITU TESTS

Locations of field-testing points have been marked at the site as per the direction of the client. These locations have been designated as BH-1 to BH-3 in this report.

2 .1.1 BOREHOLES Following operations have been carried out during the progress of boreholes :

(a) Drilling through NX size core drill machine using diamond bits through rock down to termination depth of 6.0-9.40m .

(b) Measurement of Core recoveries & Rock quality designation.

(c) Collection of rock cores from the site for

laboratory testing.

2.1.1.1 WATER TABLE

In the boreholes, groundwater was not encountered to the final explored depth of 9.40m below ground surface during the time of our field investigation (February, 2013).

RAO ENGINEERING ENTERPRISES - GEOTECHNICAL REPORT - PAGE 4 2.1 .1 .2 FIELD TEST RESULTS

Following Core recoveries & Rock quality designation values have been recorded at various depths in the three boreholes:

Borehole

No. Depth (m) Core

recoveries % RQD %

0.0-1.5 35 15

1.5-3.0 48 20

3.0-4.5 55 30 1

4.5-6.0 42 22

0.5-2.0 30 20

2.0-3.5 45 25

3.5-5.0 50 28 2

5.0-6.5 60 40

0.1-1.5 56 21

1.5-3.0 59 20

3.0-4.5 50 26

4.5-6.0 44 32

6.0-7.5 35 31

7.5-9.0 32 22

3

9.0-9.40 25 0


2.2 LABORATORY TESTS AND RESULTS

Following tests have been conducted on Rock samples in the laboratory :

ROCK SAMPLES

(a) Crushing strength (b) Point load strength index (c) Natural Moisture Content (d) Bulk Density (e) Water absorption. (f) Void Ratio & porosity. (g) Specific gravity

Note: The laboratory tests results conducted on rock samples are given on table no.4a.


3.0 OBSERVATIONS

Following points are observed from results obtained :

(a) The Quartzite (Rock) is encountered at the site from ground surface to the final explored depth of 9.40 m. It is moderately strong to strong in in quality & moderately weathered in nature. The core recovery ranges between 25 to 60 percent with 0 to 40 percent RQD.

(b) Bulk density values in rock strata vary from 2.68 to 2.71 gms/cc.

(d) The Crushing Strength ranges between 420.0-870.6 kg/cm².

(e) The RMR value of the rock ranges between 18-24.

4.0 DISCUSSIONS

For designing the foundation system, the following Parameters are required:

(a) Suitable type of foundation on which the proposed super – structure can be supported.

(b) Depth of these foundations, and

(c) Allowable bearing pressure at the founding level corresponding to various footing sizes.


4.1 TYPE & DEPTH OF FOUNDATION

Type of foundation to be adopted for a particular structure depends upon the loading intensity at the foundation level and the configuration of loading points. Reviewing the site stratigraphy & laboratory test results of the rock samples, we recommend that Isolated open spread foundation bearing at or below 1.5m depth below the existing ground surface resting on Rock formation may be provided at the site to support the structural load.

4.2 ALLOWABLE BEARING PRESSURE

Following criterion have been considered for evaluating the bearing capacity values:

(a) Settlement criteria

(b) Shear failure criterion

Shear failure condition as per I.S. 6403 has been considered for allowable bearing pressure computation.

Allowable settlement value of 50 mm has been considered for deducing shear strength value.

5.0 RECOMMENDATIONS

The following table presents our recommended Net allowable bearing pressures for 1-4 m wide Isolated Open Spread Foundation bearing at or below 1.5m depth below the existing ground surface on rock formation.

Foundation Embedment Depth (m)

Recommended Net Allowable Bearing Pressure(T/sq.m.)

1.5 23.0

2.0 26.0

The above values include a Safety Factor of 3.0.The total permissible settlement for the above recommended bearing pressures may range between 20-25 mm.


6.0 ELECTRICAL RESISTIVITY TEST RESULTS Electrical resistivity tests were conducted as per IS: 3043-1987 at the project site. The tests were conducted using the Wenner configuration along different directions at various electrode spacings ranging from 1 to 10 m. The average apparent resistivity values are presented graphically and also tabulated on Figs. 5 to 7. The test results are also tabulated below:

Average Resistivity, ohm-m Electrode

Spacing, m ERT-1 ERT-2 ERT-3 1.0 52.6 60.2 48.2 2.0 82.9 88.7 99.5 3.0 95.3 99.5 108.6 5.0 120.5 110.5 135.7 7.0 145.7 158.5 155.7 10.0 210.8 205.3 253.6

These resistivity data are used as an indicator for potential for corrosion of buried metallic pipes and other utility lines. All buried metallic pipelines be coated adequately.

7.0 CHEMICAL ATTACK

Chemical test results on soil are presented in our report on sheet no. 8. The results indicate that the soils contain sulphate in the range of 0.10 to 0.12 percent and chlorides 0.03 to 0.04 percent. The pH value of soil is between 7.2 to 7.6 indicating slightly alkaline conditions. The groundwater at the site is not met to 9.40m depth.

IS:456-2000 recommends that precautions should be taken against chemical degradation of concrete if the sulphates content of the soils exceeds 0.2 percent or if the groundwater contains more than 300 mg per litre of sulphates (SO3).

RAO ENGINEERING ENTERPRISES -- GEOTECHNICAL REPORT - PAGE 9

Comparing the test results with the specified limits in IS 456-2000, We recommend the following measures to limit the potential for chemical attack:

(1) Concrete for Open foundations should contain a minimum cement content of 330 kg/m3 of cement.

(2) Water cement ratio in foundation concrete should

be in the range of 0.50. (3) A clear concrete cover over the reinforcement

steel of at least 50mm should be provided for all foundations.

8.0 CLOSURE

We appreciate the opportunity to perform this investigation for you and have pleasure in submitting this report. Please contact us when we can be of further service to you.

For RAO ENGINEERING ENTERPRISES

(G.R.RAO) (PUSHPENDRA KUMAR) DIRECTOR EXECUTIVE DIRECTOR

WATER TABLE

Type of Boring: Rotary

Col

our

Loss

0.00 RK-1 1-3 35 151.50 1.50 Moderately weathered 20

RK: Rock core1.50 RK-2 4-6 Moderately Strong,0.0m to 3.0m 48 203.00 1.50

Dark Brown Partial3.00 RK-3 7-10 55 304.50 1.50 24

4.50 RK-4 11-15 42 226.00 1.50 (6.00m)

Project : Proposed 33KV Grid Station at Naaz Cinema (D) SRD.

Bits

Use

d

Sym

bol

DESCRIPTION

Per

cent

Rec

over

y

Roc

k Q

ualit

y D

esig

natio

n (R

QD

) (%

)

Roc

k M

ass

Rat

ing

(RM

R)

Return Water

Dep

th (m

)

Dril

l Run

(m)

Sam

ple

No.

Sei

ral N

o. o

f Cor

es

BH.No.-1 Termination Depth - 6.0 m

TABLE NO. 1

JOB NO. 5203Not Met

Moderately Strong to Strong brown Quartzite (Rock),

Strong,3.0m to 6.0m

32 C

T D

iam

ond

Impr

egna

ted

Bit

WATER TABLE


Col

our

Loss

0.00 Fill :Light Brown Fine sand0.50 0.50 DS-1 (0.50 m)

0.50 RK-1 1-3 Moderately weathered 30 20 202.00 1.50

Moderately Strong,0.5m to 3.0m RK: Rock core2.00 RK-2 4-8 45 253.50 1.50

3.50 RK-3 9-12 50 285.00 1.50 24 Dark Brown Partial

5.00 RK-4 13-16 60 406.50 1.50 (6.50 m)

5203Not Met

Strong,3.0m to 6.5m

Dep

th (m

)

Dril

l Run

(m)

Sam

ple

No.

Sei

ral N

o. o

f Cor

es

Sym

bol

DESCRIPTION

Per

cent

Rec

over

y

Roc

k Q

ualit

y D

esig

natio

n (R

QD

) (%

)

Roc

k M

ass

Rat

ing

(RM

R)

Return Water


Project : Proposed 33KV Grid Station at Naaz Cinema (D) SRD.

Bits

Use

d

BH.No.-2 Termination Depth-6.50 m

TABLE NO. 2

JOB NO.

32 C

T D

iam

ond

Impr

egna

ted

Bit

WATER TABLE


Col

our

Loss

0.00 Fill:Light Brown Fine sand0.10 DS-1 (0.10 m)

0.10 RK-1 1-3 Moderately weathered 56 21 201.50 1.40

Strong,0.1m to 7.5m RK: Rock core1.50 RK-2 4-7 59 203.00 1.50

3.00 RK-3 8-13 50 264.50 1.50

4.50 RK-4 14-16 44 326.00 1.50 22

6.00 RK-5 17-22 35 317.50 1.50 Dark Brown Partial

Moderately strong,7.5m to 9.40m7.50 RK-6 23-27 32 229.00 1.50 18

9.00 RK-7 28-30 25 09.40 0.40 ( 10.0m)

Sym

bol

DESCRIPTION

Per

cent

Rec

over

y

Roc

k Q

ualit

y D

esig

natio

n (R

QD

) (%

)

Roc

k M

ass

Rat

ing

(RM

R)

Return Water

5203Not Met

Dep

th (m

)

Dril

l Run

(m)

Sam

ple

No.

Sei

ral N

o. o

f Cor

es

Termination Depth-9.40 mProject : Proposed 33KV Grid Station at Naaz Cinema

(D) SRD.

Bits

Use

d

TABLE NO. 3

JOB NO.

BH.No.-3


32 C

T D

iam

ond

Impr

egna

ted

Bit

4

SYMBOLFill

Quartzite( Rock)

LEGEND

PROPOSED 33 KV GRID STATION AT NAAZ CINEMA (D) SRD.

3D E

P T

H,

m0

SUMMARY OF BOREHOLE

1

2

4

BH-3

9.40m

56/21

59/20

Recovery/RQD

5

50/26

6

7

8

44/32

35/31

9

1.5m

3.0m

4.5m

6.0m

7.5m

32/22

BH-1

6.00m

35/15

48/20

Recovery/RQD

55/30

42/22

1.5m

3.0m

4.5m

BH-2

6.50m

30/20

45/25

Recovery/RQD

50/28

60/40

2.0m

3.5m

5.0m

10

25/09.0m

0.5m 0.1m

5

Electode ApparentSpacing,m Resistivity, Ohm-m

1.0 52.62.0 82.93.0 95.35.0 120.57.0 145.710.0 210.8

ELECTRICAL RESISTIVITY TEST NO - 1

1

10

100

1000

0 2 4 6 8 10 12 14 16Electrode Spacing , m

App

aren

t Res

istiv

ity ,O

hm-m


6


1.0 60.22.0 88.73.0 99.55.0 110.57.0 158.510.0 205.3


1

10

100

1000


App

aren

t Res

istiv

ity ,O

hm-m


7


1.0 48.22.0 99.53.0 108.65.0 135.77.0 155.710.0 253.6


1

10

100

1000


App

aren

t Res

istiv

ity ,O

hm-m


8

SOIL :

Borehole No.

pH Value

1 7.23 7.54 7.6

0.04

CHEMICAL TEST RESULTS

Depth, (m)

Sulphate Content ,%

(SO3)

Chloride Content ,%


0.00 0.12 0.030.501.00 0.10 0.03

0.11

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