NAME OF THE PROJECT GEOTECHNICAL INVESTIGATION … · unconfined compressive strength. 5. ANALYSIS...

2017

GEOTECHNICAL INVESTIGATION REPORT

NAME OF THE PROJECT: GEOTECHNICAL INVESTIGATION STUDIES WORK FOR

ANDHRAPRADESH MEDTECH ZONE (AMTZ),

VISHAKHAPATNAM, ANDHRAPRADESH.

LOCATION: Manufacturing Unit

Borehole No.: BH‐17

Sample Ref. No: IDAX/QC/SOIL/40

Report Ref. No: IDAX/REP/ICRPL‐2017060007/EXP‐GI/2017‐18/455

TESTING AGENCY:

IDAX CONSULTING & RESEARCH PVT.LTD. Plot No. - 5016, Duplex-E, Brundaban Enclave, VSS Nagar,

Bhubaneswar-751007, Odisha (INDIA).

Tel: +91-674-3199991, 2360019, Fax: +91-674-2360019

E-mail: [email protected]

Web: www.idaxconsulting.com

Date of Test: 03.07.2017

Date of Submission of Report: 18.07.2017

mailto:[email protected]

http://www.idaxconsulting.com/

IDAX CONSULTING & RESEARCH PVT.LTD.

Project Code: 2017060007_GI Page 1 of 22

P R E F A C E

IDAX CONSULTING & RESEARCH PVT.LTD. is pleased to submit the geotechnical

investigation report for BH-17 at Manufacturing Unit, for Andhrapradesh

MedTech Zone (AMTZ), Vishakhapatnam, Andhrapradesh. The objective of this

investigation is to ascertain the characteristics of Sub-soil to present necessary

information for sub-surface. It was endeavored to study in detail the sub-surface

conditions at the project site.

The general soil profiles and the geological stratification have been determined.

The field and laboratory works have been conducted as per relevant IS Codes.

This is to certify that the samples are collected from the proposed site for the Bore

Hole – 17 for Andhrapradesh MedTech Zone (AMTZ) at Manufacturing Unit,

Vishakhapatnam, Andhrapradesh by IDAX CONSULTING & RESEARCH PVT.LTD.

VSS NAGAR, BHUBANESWAR-751007. The laboratory

tests have been performed under the supervision of qualified personal, as per the

Indian standards and this report is prepared on the basis of these tests results and

experts experience.

For IDAX CONSULTING & RESEARCH PVT.LTD.

Engineer – Civil (Soil) Er. Pratiksha Ray B. Tech- Civil

(Head - Civil)

Er. Deepak Kumar Mallick

B. Tech (Hons.) – Civil (IIT Kharagpur)



CONTENTS

Sl. No. PARTICULARS PAGES

01. INTRODUCTION 03

02. SCOPE OF WORK 03 - 04

03. DETAILS OF FIELD WORK 05

04. LABORATORY TESTS 05 - 07

05. ANALYSIS OF SUB-SOIL INVESTIGATION 07 - 08

06. DETERMINATION OF SAFE BEARING CAPACITY 08

07. DETERMINATION OF ALLOWABLE BEARING CAPACITY 08

08. FOUNDATION & RECOMMENDATION 09

09. LIMITATION 09

10. CLOSURE 09 - 10

BORE LOG & LAB TEST RESULTS OF BORE HOLE

ABP CALCULATIONS

RECORD OF BORING



1. INTRODUCTION

Intending to provide a safe, sound and economical foundation system for the Sub - Soil

Exploration work for BH-17 at Manufacturing Unit, Studies Work for

Andhrapradesh MedTech Zone (AMTZ), Vishakhapatnam, Andhrapradesh and

the work for conducting detailed soil investigation work has been awarded to Idax Consulting

& Research Private Limited, VSS Nagar, Bhubaneswar- 751007.

i. Objectives of Sub-soil Exploration

The objective of this Geo-technical investigation is to optimize the Foundation system for

proposed Project within the safe bearing capacity of the soil and allowable settlement, it

consists of the following

• Determination of type, size and depth of foundation- system by analyzing the soil

properties

• To suggest a conclusive recommendation for the type of foundation System to be adopted

which would be economically viable and structurally safe for the proposed structures of the

projects.

ii. Limitations of Investigation

The scope of Geo-technical exploration is confined within limitations of the framework of

agreement drawn between AMTZ LIMITED and IDAX CONSULTING & RESEARCH

PRIVATE LIMITED, Bhubaneswar-751007. All the field and laboratory experiments have

been carried out as per the Technical specification of the client and the relevant Indian

Standard Code of practice. However the directions issued by the authority in this respect has

been given due emphasis during the sub soil exploration work.

2. SCOPE OF WORK

The scope of work comprises of conducting detail soil investigation, laboratory testing,

conducting and estimation of safe bearing capacity for the above proposed work on drilled

borehole as shown by the Engineer-in charge.

i. Nature of Investigation Work

The all investigation consists of the following:

Visual reconnaissance of the site.

Field Work-Drilling of bore hole up to the required depth.



Laboratory experiments, determination of soil parameters.

Analysis of field and Laboratory data

Arriving at the conclusive decision on foundation system to be adopted in the present

case using Our Engineering judgment, based on the current practice. The detailed

Geo-technical investigation work that was carried out consists of two parts.

ii. Field Investigation:

The field investigation consists of the following methods

Location of One number of bore hole with due consultation with the authority.

Boring / drilling up to 10.0m depth below N.G.L or refusal.

Conducting standard penetration test (SPT) & Collection of undisturbed sample

(UDS) at the locations prefixed by the Engineer-in-charge.

Observation of the depth of water table in the Borehole.

Study of site condition and surroundings with regards to the need of the Project.

Taking observation of surrounding structure to observe any deficiency in safety.

Transportation of all soil samples to laboratory for analysis with proper care.

iii. Laboratory Tests:

The Laboratory tests for the sample collected are given below

Determination of Grain size analysis

Determination of soil moisture content

Determination of liquid limit

Determination of plastic limit

Determination of specific gravity

Determination of Allowable Bearing Pressure of Rock.



3. DETAILS OF FIELD WORK

i. Selection of Borehole:

One Bore-hole was selected by the Engineer in charge in order to obtain comprehensive

sub-soil data for this site with a provision of borings up to 10.0m depth as required as per

IS:1892 - 1979. For detailed laboratory investigation SPT is conducted @ 1.0 m intervals or

at change of soil Strata in different Boreholes and S.P.T soil samples were collected for

laboratory analysis. Disturbed representative, soil samples from all the Boreholes were

collected at 1.0 m. interval for different tests.

ii. Boring:

It is the main part of sub soil investigation work as the soil samples were collected for

different tests at different levels. The sub-soil exploration work at the proposed site was

carried out manually / mechanically using 150 mm diameter shell and auger manual

equipment in soft strata and power operated Mechanical boring in hard strata using diamond

cutter , as per IS : 1892 – 1979 .

iii. Standard Penetration Tests:

Standard penetration test plays a major role in sub soil investigation termination of safe

bearing capacity of soil in non cohesive type soil, particularly in non-cohesive granular sandy

soil and where the UDS could not be collected either due to high liquidity or non cohesive

nature of soil .The SPT tests were conducted as per IS: 2131-1981 respectively. The SPT

sampler was lower inside the borehole after drilling the required level and is driven by a

63.50 kg Rammer with a free fall of 750 mm. driving 450 mm in One stages 150 mm each

and the number of blows for each 150mm penetration for 2nd & 3rd 150 mm drive recorded

as “N”. Refusal was considered for N>100. The details of location of test and SPT value [N]

are presented in bore log data annexed separately.

iv. Ground Water Table:

During exploration work of the Location, 24hours observation it is found that the water table

is at 2.15m depth in BH-17 within the Boring depth from the existing ground level depending

on the location of boring. The water table may be fluctuating due to change of season.

4. LABORATORY TESTS

The laboratory-tests were conducted on selected representative disturbed / undisturbed soil

samples collected from different Borehole drilled at the proposed site. The tests include

Grain size analysis, Natural moisture content, D.F.S, Specific Gravity and Liquid limit, Plastic

limit, Plasticity index, Shear test, and Particles size distribution tests on representative soil



sample were also carried out. All the tests conducted confirming to the requirements of I.S

specification. The results of all these tests have been annexed separately.

i. Grain Size Analysis:

The grain size analysis of different soil samples were done as per the requirement of IS:

2720 (Pt-IV) 1985 – method of test for soil, Grain size analysis. The details of the test results

are shown test result sheet separately. The results of grain size analysis are used to classify

the soil in various depths of boreholes. The results of all these tests have been annexed

separately.

ii. Natural Moisture Content:

The natural moisture content was determined from different undisturbed samples of different

Boreholes at different depths, as per IS: 2720(Pt-II)-1973: Method of test for soil,

determination of Water content.

iii. Determination of Specific Gravity:

The specific gravity of the UDS / DS samples have been determined at different levels as

per IS: 2720 (Pt-III) - 1980. It is used for determining void ratio, porosity, saturated density,

S.B.C, settlement of foundation system. The results of all these tests have been annexed

separately.

iv. Determination of Void Ratio:

The void-ratio of the UDS / DS samples has been determined at different levels and the

results are shown separately. It is used for determining specific gravity, optimum moisture

content, S.B.C, settlement of foundation system. The results of all these tests have been

annexed separately.

v. Determination of Liquid Limit / Plastic Limit:

The liquid and plastic limits of soils were other index properties of soil have also been

determined as per the relevant as per IS: 2720(Pt-v)-1985 Code of practice. The liquid and

plastic limits of soil samples have been determined in the laboratory and it is used for

determining S.B.C, settlement of foundation system etc. The results of all these tests have

been annexed separately.

i. Core Recovery:

Rock core samples are kept in the same order as recovered from bore hole run wise

(marked arrow on cores in the increasing order of depth). The length of all core samples is



measured. Core recovery is the ratio of the sum of the lengths of all the cores recovered

from drilling per run.

Core Recovery (%) = (Total length of core pieces recovered/Length of run x 100

It is expressed in percentage (%).

ii. RQD:

Rock Quality Designation indicates the quality of the rock. RQD is defined as the ratio of the

sum of the total length of the cores of length 10cm and longer recovered from the drilling of

the total length of the borehole is 1.5m.

RQD = (Total length of cores in pieces of 10cm length or longer/length of the run) x 100

It is expressed in percentage (%).

iii. Unconfined compressive strength of rock specimens:

As soon as the rock core samples were received in the laboratory, Core Recovery

percentages and RQD percentages were determined. Then core samples which were longer

than the diameter that was 54mm were selected for preparation of specific specimens as per

IS: 9143-1979 in the ratio of length : diameter = 1:1 and correction factors applied ( since

limited intact rock core sampling was possible). Then the specimens were tested for

unconfined compressive strength.

5. ANALYSIS OF THE SUB-SOIL INVESTIGATION

LOCATION: Vishakhapatnam, Andhrapradesh

CO-ORDINATES:- N: 1950347.006, E: 729089.003 RL: 37.0mtr.

Borehole No. - 17 was have explored up to a depth of 10.0m the sub soil strata of the

Borehole is summarized as follows.

LAYER- 1

The layer starts from 0.0m to 3.0m & 5.0m to 8.0m consists of ‘Poorly Graded Clayey Sand’.

The soil sample in this layer was tested and results are summarized. The average weight

was Gravel- 1%, Sand- 56%, and Silt & Clay- 43%. The engineering classification of the soil

is SC as per IS: 1498-1970.

LAYER-2

The layer starts from 3.0m to 4.0m consists of ’Poorly Graded Gravel’. The soil sample in

this layer was tested and results are summarized. The average weight was Gravel- 53%,

Sand- 42%, and Silt & Clay- 5%. The engineering classification of the soil is GP as per IS:

1498-1970.



LAYER- 3

The layer starts from 4.0m to 5.0m which is followed by ‘Moderately Strong’ Strata. The core

recovery at 5.0m is 18% & RQD is Nil, respectively. The engineering classification of the

Rock from 4.0m to 5.0m depth is Moderately Strong UCS (in MPa) 12.5 to 50.0 as per

IRC: 78-2014.

LAYER- 4

The layer starts from 8.0m to 10.0m consists of’ Poorly Graded Sand’. The soil sample in

this layer was tested and results are summarized. The average weight was Gravel- 0%,

Sand- 96%, and Silt & Clay- 4%. The engineering classification of the soil is SP as per IS:

1498-1970.

6. DETERMINATION OF SAFE BEARING CAPACITY (SBC)

Borehole

Depth in mtrs.

Net Safe Bearing Capacity in T/m2.

Gross Safe Bearing Capacity in T/m2.

BH – 17

1.0 10.29 11.29

2.0 46.24 48.24

3.0 49.11 52.31

4.0 116.94 120.94

7. DETERMINATION OF ALLOWABLE BEARING PRESSURE OF

(ABP)

The allowable bearing pressure has been calculated as per IS: 2131 & IS: 8009 (Part-I) at

different depth from the existing ground level. The details of the calculation are annexed

separately.

Borehole- 17

Depth in mtrs.

Allowable Bearing Pressure in T/m2

25mm 40mm 75mm

2.0 18.54 29.67 55.63

4.0 27.23 43.58 81.70

6.5 33.36 53.37 100.07

8.0 35.47 56.75 106.40

9.0 36.49 58.38 109.47

10.0 46.31 74.10 138.94



8. FOUNDATION & RECOMMENDATION

Based on our field and laboratory investigation, the following recommendations are made:

i. The stratum encountered in different boreholes at different depths is presented in

respective soil profile sheets.

ii. The water table if encountered in the boreholes is also indicated in the soil profile

sheets.

iii. The depth of foundation shall be decided based on bearing capacity and uplift

resistance required.

iv. The recommended safe bearing capacity for the footing is computed based on

footing size as specified for suggested foundations are given below.

v. As per site condition which, visual observations of soil samples at site, field bore log

record, local geology of the area, type of sample received, laboratory classification of

soil samples and based on the experience of our Geotechnical Expert, it is

recommended to provide open foundation.

vi. The recommended safe bearing capacity for the footing is computed based on

footing size as specified for suggested foundations are given below. It is feasible to

provide open foundations. Open foundations can be placed at a depth of 3.0m below

the existing ground level. However for heavily loaded structures the foundation depth

can be increased as per the design load.

9. LIMITATION

The soil investigation has been carried out at the location chosen by the client.

Recommendations made in the report are hence valid only for these tests locations.

However if there is any change in subsoil conditions and properties at places beyond chosen

test locations, the soil consultants be contacted for further guidance.

10. CLOSURE

We appreciate the opportunity given to us to submit this draft report. This presented report is

based on observations and tests on samples collected from the boreholes as decided by the

client. In case any difference is noticed in the field subsoil strata and reported subsoil strata

during excavation please contact us before proceeding with further construction.



NB:

The above test reports are based on the sample received by our laboratory.

The test results relates only to the items tested.

The report shall not be reproduced except in full without the approval of the testing

laboratory.

For IDAX CONSULTING & RESEARCH PVT.LTD.

Engineer – Civil (Soil) Er. Pratiksha Ray B. Tech- Civil

(Head - Civil)

Er. Deepak Kumar Mallick

B. Tech (Hons.) – Civil (IIT Kharagpur)



BORE LOG AND LAB TEST RESULT OF BOREHOLE



BORE HOLE -17

Type of Soil

Soil

Profile

Depth

in mtrs.

SPT Value "N" Depth Plot

N

Type of

Sample

Core

Recovery

(%)

R.Q.D

(%)

N1 - N2 - N3

0.00

SC

GP

SC

SP

0 10 20 30 40 50 60 70 80 90 100

0.0

Poorly graded

1.0

clayey sand

2.0 35

12-14-21

SPT Sample

WL:

2.15 m

3.0

Poorly graded

gravel 4.0

50 >50 SPT Sample

Moderately

strong

5.0 18% Nil

6.0

Poorly graded

clayey sand

7.0

63 22-28-35

SPT Sample

8.0

71

26-31-40

SPT Sample

Poorly graded

9.0

78

28-36-42

SPT Sample

sand

10.0 100

>100

SPT Sample

TABLE ‐ 1

SUMMARY SHEET RESULT OF SOIL SAMPLE

LOCATION: MANUFACTURING UNIT CLIENT: AMTZ LIMITED

CO‐ORDINATES:‐ N: 1950347.006 E: 729089.003 RL: 37.0 mtr

L O

CA

T I

O N

No

.

Sa

m p

lin

g D

epth

(m

)

T y

pe

of

s a

m p

le

SP

T V

a lu

e (

N )

Grain size analysis

D .

F .

S .

In

%

Atterberg’s Limits

C la

s s

ific

a t

ion

of

S o

il

Density test

N a

tu ra

l M

o is

tu

re c

o n

ten

t(%

)

Sp

eci

fic

gra

vity

Shear Parameters

Vo

id R

a t

io (

e o

)

Pe

rm

ea

bili

ty T

e s

t

in c

m /

se c

G r

av

el in

%

(2 0

m m

- 4

.75

m m

)

C o

ars

e S

an

d in

%

(4 .7

5m

m -

2m

m )

M e

diu

m S

an

d in

%

(2 m

m -

.4

25

m m

)

F in

e S

and

in

%

(.4

25

m m

- .

07

5m

m )

S ilty

& C

la

y in

%

(.0

75

m m

P a

ss

in g

)

Liq

uid

Lim

it

(% )

Pla

s tic

Lim

it

(% )

Pla

s ti

c it

y I

nd

ex

(%

)

Bu

lk d

en

s it

y in

g

m /

c c

.

D r

y d

en

s it

y in

g

m /

c c

.

T y

pe

of

T e

s t

C o

he

s io

n (

C )

Kg

/c m

2

An

gle

of in

te r

na

l

fric

tio

n( φ

) in

D e

gre

e

BH No.-17

0.0 DS - 0.00 1.68 19.87 36.54 41.91 20 33 20 13 SC

13.27 2.61

1.0 UDS - 0.00 0.00 15.32 41.02 43.66 20 35 22 13 SC 1.905 1.638 16.33 2.60 TA 0.24 8 0.59 0.66x10‐5

2.0 SPT 35 3.65 18.97 32.05 6.33 39.00 15 31 19 12 SC

14.36 2.67

3.0 UDS - 6.05 26.98 19.94 9.35 37.68 10 30 20 10 SC 1.983 1.711 15.87 2.65 DS 0.18 25 0.55

4.0 SPT >100 53.24 21.05 16.02 4.97 4.72 0 20 NP NP GP

13.57 2.74

6.5 SPT 63 0.00 0.00 11.78 42.36 45.86 20 33 21 12 SC

16.35 2.58

8.0 SPT 71 0.00 15.36 20.74 15.23 48.67 25 35 20 15 SC

18.21 2.64

9.0 SPT 78 0.00 0.00 20.47 74.89 4.64 0 24 NP NP SP

15.24 2.55

10.0 SPT >100 0.00 5.64 32.74 57.38 4.24 0 21 NP NP SP

15.67 2.55

IDA

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ALLOWABLE BEARING PRESSURE (ABP) AND SAFE

BEARING CAPACITY (SBC) OF SOIL



CALCULATION OF ALLOWABLE BEARING PRESSURE (ABP) FOR

SETTLEMENT CRITERIA

Project Name: GEOTECHNICAL INVESTIGATION FOR AMTZ LIMITED

Location: MANUFACTURING UNIT Project Code: 2017060001-GI

Bore Hole No.: 17 Water Table: 2.15 mtrs

References Calculations

IS:8009 (Part-I) Input Data

Width / Diameter of Footing (Assumed) B = 2 mtr.

Length of Footing (Assumed) L = 2 mtr.

Shape of the Foundation = SQUARE Influence Zone below foundation level = 3.00 mtr.

Type of Soil Strata = Elastic/Immediate (For Sandy & Granular Strata)

Type of Foundation = Flexible Foundation

Fig-11 Correction Factor for Rigidity Cr = 1.0

Water Table depth below GL = 2.15 mtr.

Fig-9 Water Table Factor to be Considered ? = Worst Condition Scenario (Submerged)

Fig-12

Fox's Depth Factor to be Considered ?

Cd

=

YES

Depth to be ignored in Depth Factor

Computation for loose soils, poorly

compacted backfill, scour, etc. = 0 mtr.

SP

T C

ond

ucte

d a

t D

epth

in

m tr.

Fie

ld S

PT

Valu

e (

N)

W id

th o

f F

oo

tin

g in

M .

(Assu

m e

d)

Correction of

Co

rre

sp

on

din

g s

ett

lem

en

t in m

m fo

r

1kg/c

m2 a

s p

er

IS: 80

09 (

Part

-I)

Fig

-

9 (

Si)

Co

rre

ctio

n F

acto

r fo

r W

ate

r T

ab

le a

s

per

IS:8

009 (

Part

-I)

Cw

Fox C

orr

ectio

n for

Depth

as p

er

IS:8

009 (

Part

-I),

Fig

-12 C

d

Fin

al C

orr

ecte

d S

ett

lem

en

t in

m

m S

=S

ixC

dxC

r/C

w m m

se

ttle

m e

nt

in

T/m

2.

m m

se

ttle

m e

nt

in

T/m

2.

m m

se

ttle

m e

nt

in

T/m

2.

SPT values

(IS:2131-1981)

Corr

ecte

d S

PT

va

lue

due t

o o

ver

burd

en

pre

ssure

(N

')

Corr

ecte

d S

PT

va

lue a

s

per

Dila

tancy (

N")

25

40

75

N Value >3

AB

P f

or

AB

P f

or

AB

P f

or

2.00 35 2 35.00 25.00 9.93 0.54 0.73 13.48 18.54 29.67 55.63

4.00 50 2 50.00 32.50 7.40 0.50 0.62 9.18 27.23 43.58 81.70

6.50 63 2 58.59 36.80 6.46 0.50 0.58 7.49 33.36 53.37 100.07

8.00 71 2 60.35 37.70 6.29 0.50 0.56 7.05 35.47 56.75 106.40

9.00 78 2 62.40 38.70 6.12 0.50 0.56 6.85 36.49 58.38 109.47

10.00 100 2 80.00 47.50 4.91 0.50 0.55 5.40 46.31 74.10 138.94

( U n

s o

a k

ed /

S o

ak

ed )

(K N

)

(T o

n )

(K g

/ c m

2 )

C o

n s

i d

e r

i n g

Fa

c t o

r o

f

(T o

n /

m 2 )

(M p

a )

p e

r I R

C :

78

- 2

01

4

TEST RESULT OF ROCK SPECIMEN As per IS: 1121

Bore Hole No:- 17

S l

. N o

.

D e

p t

h of

S a

m p

l e

( m t

r )

T

e s

t C o

n d

it io

n

D

i a

o f t

h e

S a

m p

l e

(c m

)

Le n

g t h

of t

h e

S a

m p

l e

( c m

)

A

r e

a ( c

m 2 )

Unconfined compressive Strength

C

l as

s i

f i c

a t

i o n

o f

R o

c k

as

Lo

a d

Lo

a d

C r

us

h i

ng

S t

r e

n g

t h

C r

us

h i n

g S

t r e

n g

t h

a f t

e r

S a

fe

ty

U

C S

1

4.00 to 5.00

Soaked

5.4

5.4

22.90

33.5

3.35

146.45

183.06

14.64

Moderately Strong

The above test results pertains to the sample received by the Laboratory

Note : Considering Factor of Safety = 8 as per IRC: 78 - 2014.

IDA

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ON

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& R

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Project Code: 2017060007_GI

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CALCULATION OF SAFE BEARING CAPACITY (SBC) Based on C, • Value


Location: MANUFACTURING UNIT Project Code: 2017060007 - GI

Bore hole no.: 17 Depth of Sample: 3.00 mtrs Water Table: 2.15 mtrs


IS:6403, Table -1

Input Data

Cohesion C = 0.18 Kg/cm2 Depth of Foundation Df = 3.00 mtr.

Angle of internal friction Ф = 25 Degrees

tan-1 ( 0.67 tanФ ) Ф' = 17 Degrees

Bulk Density = 1.983 gm/cc Field Moisture Content = 15.87 %

Dry Density γd = 1.711 gm/cc Specific Gravity Gs = 2.65

Saturated Density γsat = 2.065 gm/cc Void Ratio e = 0.55

Submersible Density γs = 1.065 gm/cc



Type of Footing = Square Footing

Condition of Soil = Medium

Overburden Pressure

q = (Df x γs) / 1000 = 0.320 Kg/cm2 Bγ =( B x γs) / 1000 = 0.213 Kg/cm2

Bearing Capacity Factors

Shape Factors For Square Footing Water Table Effect

Sc = 1.3 Sq = 1.2 Sγ = 0.8 W' = 0.5

Depth Factors Inclination Factors

dc = 1+0.2 x (Df/B) x tan(45+Ф/2) = 1.471 ic = iq = iγ = 1

dq = dγ = 1.235

In case of general shear failure Net Ultimate Bearing Capacity

qd = CNcScdcic + q(Nq -1) Sqdqiq + 0.5 BγNγSγdγiγW'

= 7.132 + 4.574 + 0.572 = 12.278 Kg/cm2

In case of Local shear failure Net Ultimate Bearing Capacity

q'd = 2/3 x CN'cScdcic + q(N'q -1)Sqdqiq + 0.5 BγN'γSγdγiγW'

= 2.873 + 1.858 + 0.197 = 4.928 Kg/cm2

After Interpolating, Net Ultimate Bearing Capacity Qnu = 12.278 Kg/cm2

Soil Bearing Capacity (SBC)= Qs = Qnu / FS + OB Factor of Safety (FS) = 2.5

Qs= 5.231 Kg/cm2 = 52.31 Tons/m2

Net Safe Bearing Capacity (NSBC)= Qns = Qnu / FS = Qs - OB

Qns= 4.911 Kg/cm2 = 49.11 Tons/m2

IS:6403, Table -2

Dense

Loose

Medium

SBC = 52.31 Tons/m2 NSBC = 49.11 Tons/m2

Ф Nc Nq Nγ

25 20.720 10.660 10.880

Ф' N'c N'q N'γ

17 12.520 4.924 3.746



CALCULATION OF SAFE BEARING CAPACITY (SBC) Based on SPT "N" Value



Bore Hole No.: 17 Depth of Sample: 2.00 mtrs Water Table: 2.15 mtrs


IS:2131, Fig-1

Input Data

Field SPT Value N = 35

Depth of Foundation Df = 2.00 mtr.

Corrected SPT value after over burden pressure N' = 45.500

Corrected SPT value after Dilatancy N" = 30.250

Angle of internal friction based on SPT "N" Value Ф = 35.7 Degrees


Submersible density (Assumed) γs = 1.000 gm/cc




Condition of Soil = Dense

Overburden Pressure




Sc = 1.3 Sq = 1.2 Sγ = 0.8 W' = 0.5



dq = dγ = 1.195

In case of general shear failure Net Ultimate Bearing Capacity C = 0


= 0.000 + 9.264 + 2.296 = 11.560 Kg/cm2



= 0.000 + 0.000 + 0.000 = 0.000 Kg/cm2

Net Ultimate Bearing Capacity Qnu = 11.560 Kg/cm2


Qs= 4.824 Kg/cm2 = 48.24 Tons/m2


Qns= 4.624 Kg/cm2 = 46.24 Tons/m2

IS:6403, Fig-1

IS:6403, Fig-1

IS:6403, Table -1

IS:6403, Table -2

Dense

Loose

Medium


Ф Nc Nq Nγ

36 46.120 33.300 48.030

Ф' N'c N'q N'γ

26 22.628 12.208 13.184



CALCULATION OF SAFE BEARING CAPACITY (SBC) Based on C, • Value



Bore hole no.: 17 Depth of Sample: 3.00 mtrs Water Table: 2.15 mtrs


IS:6403, Table -1

Input Data

Cohesion C = 0.18 Kg/cm2 Depth of Foundation Df = 3.00 mtr.

Angle of internal friction Ф = 25 Degrees


Bulk Density = 1.983 gm/cc Field Moisture Content = 15.87 %

Dry Density γd = 1.711 gm/cc Specific Gravity Gs = 2.65

Saturated Density γsat = 2.065 gm/cc Void Ratio e = 0.55

Submersible Density γs = 1.065 gm/cc




Condition of Soil = Medium

Overburden Pressure




Sc = 1.3 Sq = 1.2 Sγ = 0.8 W' = 0.5



dq = dγ = 1.235

In case of general shear failure Net Ultimate Bearing Capacity


= 7.132 + 4.574 + 0.572 = 12.278 Kg/cm2



= 2.873 + 1.858 + 0.197 = 4.928 Kg/cm2

After Interpolating, Net Ultimate Bearing Capacity Qnu = 12.278 Kg/cm2


Qs= 5.231 Kg/cm2 = 52.31 Tons/m2


Qns= 4.911 Kg/cm2 = 49.11 Tons/m

2

IS:6403, Table -2

Dense

Loose

Medium

SBC = 52.31 Tons/m2

NSBC = 49.11 Tons/m

2

Ф Nc Nq Nγ

25 20.720 10.660 10.880

Ф' N'c N'q N'γ

17 12.520 4.924 3.746



CALCULATION OF SAFE BEARING CAPACITY (SBC) Based on SPT "N" Value



Bore Hole No.: 17 Depth of Sample: 4.00 mtrs Water Table: 2.15 mtrs


IS:2131, Fig-1

Input Data

Field SPT Value N = 50

Depth of Foundation Df = 4.00 mtr.

Corrected SPT value after over burden pressure N' = 54.000

Corrected SPT value after Dilatancy N" = 34.500

Angle of internal friction based on SPT "N" Value Ф = 36.9 Degrees


Submersible density (Assumed) γs = 1.000 gm/cc




Condition of Soil = Dense

Overburden Pressure




Sc = 1.3 Sq = 1.2 Sγ = 0.8 W' = 0.5



dq = dγ = 1.4

In case of general shear failure Net Ultimate Bearing Capacity C = 0


= 0.000 + 25.859 + 3.377 = 29.236 Kg/cm2



= 0.000 + 0.000 + 0.000 = 0.000 Kg/cm2

Net Ultimate Bearing Capacity Qnu = 29.236 Kg/cm2


Qs= 12.094 Kg/cm2 = 120.94 Tons/m2


Qns= 11.694 Kg/cm2 = 116.94 Tons/m2

IS:6403, Fig-1

IS:6403, Fig-1

IS:6403, Table -1

IS:6403, Table -2

Dense

Loose

Medium


Ф Nc Nq Nγ

37 51.958 39.480 60.306

Ф' N'c N'q N'γ

27 24.506 13.756 15.488



CHEMICAL TEST REPORTS:

WATER SAMPLES: (BH-17)

PARAMETERS

UNIT

RESULTS

pH Moles/H+ ions 6.85

CONDUCTIVITY s/cm 238

TDS ppm 119

CHLORIDE (CL) mg/ltr 17.99

HARDNESS (CaCo3) mg/ltr 72

TURBIDITY NTU 66.5

ALKALINITY mg/ltr 75

SOIL SAMPLES: (BH-17)

PARAMETERS UNIT RESULTS

pH

Moles/H ions

6.45

CONDUCTIVITY s/cm 278.5

CHLORIDE mg/l 136.4

SULPHATE mg/l 95.8

TOTAL SOLUBLE SOLID mg/l 76.3



RECORD OF BORING FROM FIELD

(TO BE GIVEN LETER)

NAME OF THE PROJECT GEOTECHNICAL INVESTIGATION … · unconfined compressive strength. 5. ANALYSIS...

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Transcript of NAME OF THE PROJECT GEOTECHNICAL INVESTIGATION … · unconfined compressive strength. 5. ANALYSIS...