The report summarizes a geotechnical investigation conducted for the construction of a flyover at NH-89 Ch:0+620 in Rajasthan, India. Two boreholes were drilled to a depth of 15m and standard penetration tests were conducted. The subsurface soils generally consisted of gravelly sand mixed with boulders. Laboratory tests showed the soils were non-plastic with negligible swelling pressure. Based on shear strength parameters and settlement analyses, the recommended safe bearing capacities range from 16.91 to 62.93 t/m2 depending on foundation depth. Proper compaction should be used for any backfilling.

1. Geotechnical Investigation Report- Flyover at ch:0+620
Page 1
GEOTECHNICAL INVESTIGATION
FOR CONSTRUCTION OF FLYOVER
AT CH:0+620, NH-89.
PROJECT:
CONSTRUCTION OF LEFT OUT WORKS OF AJMER-NAGAUR SECTION
OF NH-89 (Km 0.000 to Km 148.250) BY TWO LANING WITH PAVED
SHOULDER IN THE STATE OF RAJASTHAN ON ENGINEERING,
PROCUREMENT & CONSTRUCTION (EPC) MODE MINISTRY.
CLIENT: GOVERNMENT OF RAJASTHAN
PUBLIC WORKS DEPARTMENT
ON BEHALF OF
MINISTRY OF ROAD TRANSPORT & HIGHWAYS
PWD - AJMER (RAJ.)
AGENCY: BALAJI DAYALPURA INFRA PRIVATE LIMITED.
A3, CHANDRAVARDAI NAGAR, AJMER RAJASTHAN,
DATE OF REPORTING: 26.SEPTEMBER.2020
Prepared & Submitted By:
JODHPUR ENGINEERING CONSULTANTS & RESEARCH CENTRE,
83 SARDAR CLUB SCHEME, JODHPUR-342011
E.Mail : sd.thalor@gmail.com
Ph:- 09610445555

2. Geotechnical Investigation Report- Flyover at ch:0+620
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SOIL INVESTIGATION REPORT
INTRODUCTION
It has been proposed to construct a Flyover at NH-89, Ch:0+620 of
"CONSTRUCTION OF LEFT OUT WORKS OF AJMER-NAGAUR SECTION OF
NH-89 (Km 0.000 to Km 148.250) BY TWO LANING WITH PAVED SHOULDER IN
THE STATE OF RAJASTHAN ON ENGINEERING, PROCUREMENT &
CONSTRUCTION (EPC) MODE MINISTRY”. The work of soil investigation was
awarded to M/s Jodhpur Engineering Consultants and Research Centre, 83
Sardar Club Scheme, Jodhpur.
The report covers the results of the subsoil investigation carried out at the proposed
location. Work of sampling and SPT for boreholes was done during 18 July2020 to
25 July2020.
SCOPE OF THE WORK
The purpose of the soil investigation was to evaluate subsoil characteristics by
conducting in-situ and laboratory tests of the soil so as to develop recommendations
for the foundation design. The scope of the work assigned to us consisted of:
(i) Drilling Two bore holes of 150mm diameter and conducting Standard Penetration
Test (SPT) in each bore hole upto 15.0m depth as required as per Indian
Standard Specifications (IS-2131) and determination of safe bearing capacity.
(ii) Extracting disturbed / undisturbed soil samples for laboratory testing.
(iii) Conducting in-situ density determination.
(iv) Carrying out the following laboratory tests on the samples:
 Particle size distribution.
 Dry Density of soil.
 Atterberg limits.
 Shear strength test (Direct Shear Test).
 Swelling Pressure & Shrinkage Characteristics.
(v) Performing engineering analysis of all the field and laboratory data so as
to arrive at safe bearing capacity of the soil.

3. Geotechnical Investigation Report- Flyover at ch:0+620
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SOIL INVESTIGATION AND STANDARD PENETRATION TEST
The subsurface investigation in the field involve three basic operations: drilling,
sampling and conducting the required field tests. This is followed by operations in the
laboratory for conducting necessary tests.
Drilling Bore Hole
Two bore holes of 150mm diameter and 15.0m depth was drilled at the location of
the proposed site with the help of a rotary drilling rig as informed by the engineer-in-
charge.
No Water table found upto depth explored. It is expected to be at deeper depths as
informed by local peoples.
Standard Penetration Test (N -values)
The standard penetration test was conducted in the bore hole following the standard
procedure as per Indian Standard: IS 2131. The test was performed by means of a
standard split spoon sampler.
Laboratory Tests
The laboratory tests were conducted following the relevant IS code (IS:2720) for soil
tests as per the test procedure given in SP 36 (Part I) {Compendium of Indian
Standards on Soil Engineering. Part-I Laboratory Testing of Soils for Civil
Engineering Purpose, Bureau of Indian Standards}
 Particle size distribution.
 Dry Density of soil.
 Atterberg limits.
 Shear strength test (Direct Shear Test).
 Swelling Pressure & Shrinkage Characteristics.
The test results are presented in Annexure-II
BEARING CAPACITY DETERMINATION
The present case is that of a foundation of shallow depth placed in a cohesionless
deposit of soil. Two methods have been used to determine the safe bearing capacity
of the subsoil. They are based on shear failure (IS: 6403 –1981) and settlement
criteria (Peck et al 1974). The bearing capacity calculated on the basis of shear
failure criterion is based on angle of shearing resistance, Ф.
The calculation are shown in Annexure -I and results are presented in Table-1 in
Annexure-I

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DISCUSSION AND RECOMMENDATIONS
Standard Penetration Tests have been conducted upto 15.0m from ground surface.
The data from the bore holes drilled at site reveal that there is gravelly sand mixed
with Boulders upto depth explored.
Swelling pressure test shows negligible swelling pressure.
Soil strata is Non Plastic in nature,
Soil is not critical to structures.
Recommended Safe Bearing Capacity Values are as follows
Location : 1 to 2 .
Width of Foundation (B) = 4.0m
Depth
of
Foundation
Shear Failure
Criteria
Settlement Criteria
(c- Ф method) Peck et al IS: 8009
1.5m 19.70 16.91 17.86
3.0m 40.71 41.00 41.67
4.0m 48.12 41.00 41.67
5.0m 55.52 41.00 41.67
6.0m 62.93 41.00 41.67
Backfilling of the soil should be done with proper compaction.
The above recommendations are based on the field and laboratory tests conducted
on the soil and our experience in this regard. If the actual subsoil conditions during
excavation for the foundation differ from the observations reported here, the design
experts / consultants should be referred to for suggestion and for further
investigation.
For Jodhpur Engineering Consultants
And Research Centre
(Er. Sahdeo Thalor)

5. Geotechnical Investigation Report- Flyover at ch:0+620
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Annexure-I
CALCULATION FOR SAFE BEARING CAPACITY
1.Shear Failure Criteria:
The safe bearing capacity has been calculated from shear parameters for the vertical
load. Assumptions and formula used in calculation as per IS : 6403 – 1981.
The net ultimate bearing capacity in case of shear failure is given by:
qa = (1/3)* {q (Nq – 1)Sq dq iq + (1/2) Υ B NΥ sΥ dΥ iΥ)}
Where q = effective overburden pressure,
B = width of foundation,
Nc, Nq, NΥ, = bearing capacity factors depend on Ф (values as per IS),
Υ = density of soil,
Factor of safety against shear = 3
Mixed Shear Failure considered.
Shape, Depth and Inclination factors are assumed to be unity.
Lowest value of Ф in boreholes, taken for calculation purposes.
Calculation:
Location : 1 to 2.
Ф= 30 ˚ Фm= 21.05 ˚
c= 0 Nc= 19.440
B= 4 m Nq= 9.931
Y= 1.74 g/cc Ny= 10.285
Ф= 31.4 ˚ Фm= 22.14 ˚
c= 0 Nc= 24.164
B= 4 m Nq= 13.765
Y= 1.74 g/cc Ny= 15.951
Depth (m) Safe Bearing Capacity (t/m2)
1.5m 19.70
3.0m 40.71
4.0m 48.12
5.0m 55.52
6.0m 62.93

6. Geotechnical Investigation Report- Flyover at ch:0+620
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Annexure-I
2. Safe Bearing Capacity : Settlement Criteria
The standard penetration tests were conducted at the site to determine the SPT N –
values. The observed and corrected N–values have been presented in Tables in
Annexure-II. The safe bearing capacity for 25mm of settlement of the foundation (qa)
can be represented by the following equation (Peck et al 1974):
qa = 1.025 Nn X Rw
Nn = C0 N
C0 = from chart as per IS: 21310.
Rw = water reduction factor = 0.5 to 0.8, as SPT done in saturated condition.
Calculation:
Location : 1 to 2.
Depth
(m)
Nn qa = 1.025 Nn X Rw
SBC
(t/m2)
1.5m 33 16.91 16.91
3.0m 50 41.00 41.00
4.0m 50 41.00 41.00
5.0m 50 41.00 41.00
6.0m 50 41.00 41.00

7. Geotechnical Investigation Report- Flyover at ch:0+620
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Annexure-I
3. Safe Bearing Capacity : Settlement Criteria Based On IS : 8009.
The net safe bearing capacity (qa) for a total settlement of 25mm has been calculated
as per IS 8009, The computed values of safe bearing capacity are given below.
Calculation:
Location : 1 to 2.
Depth
(m)
Nn
Settlement
for
Pressure
intensity
of
1kg/cm2
Pressure for
25 mm
settlement
(t/m2)
SBC
(t/m2)
1.5m 33 7.0 35.71 17.86
3.0m 50 4.8 52.08 41.67
4.0m 50 4.8 52.08 41.67
5.0m 50 4.8 52.08 41.67
6.0m 50 4.8 52.08 41.67

8. Geotechnical Investigation Report- Flyover at ch:0+620
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TABLE-1 : SUMMARY OF SAFE BEARING CAPACITY VALUES:
Location : 1 to 2.
Width of Foundation (B) = 4.0m
Depth
of
Foundation
Shear Failure
Criteria
Settlement Criteria
(c- Ф method) Peck et al IS: 8009
1.5m 19.70 16.91 17.86
3.0m 40.71 41.00 41.67
4.0m 48.12 41.00 41.67
5.0m 55.52 41.00 41.67
6.0m 62.93 41.00 41.67

9. Geotechnical Investigation Report- Flyover at ch:0+620
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Annexure-II
TABLE-2 SOIL CHARACTERISTICS (BH-1)
Size of Hole: 150mm for Soil Strata & Nx Size for Rock, Period: 18 July2020 to 25 July2020
Depth
from
GL
(m)
Observed
N-
values
Corrected
N
n
Core
Recovery
%
RQD
%
Unconfned
Comp.Stren
gth
(t/m2)
Return Water
Dry
Density
Grain Size Distribution %
Plastic
Characteristics
Shear Strength
Parameters
Colour
Loss
%
Gravel Sand
Silt /
Clay Size
LL PL
C’
kg/cm2 Ф
1.50 22 31 0 0 -- Brownish 35 1.74 16 75 9 NP 0.0 30.0
3.00 R* 50 0 0 -- Brownish 25 1.74 14 76 10 NP 0.0 31.4
4.50 R* 50 0 0 -- Brownish 25 1.75 15 73 12 NP 0.0 32.8
6.00 R* 50 0 0 -- Brownish 25 1.75 38 52 10 NP 0.0 32.9
7.50 R* 50 0 0 -- Brownish 25 1.76 42 49 9 NP 0.0 33.1
9.00 R* 50 0 0 -- Brownish 25 1.76 45 44 11 NP 0.0 32.9
10.50 -- -- 0 0 -- Brownish 25 1.76 -- -- -- -- -- --
12.00 -- -- 0 0 -- Brownish 25 1.76 -- -- -- -- -- --
13.50 -- -- 0 0 -- Brownish 25 1.76 -- -- -- -- -- --
15.00 -- -- 0 0 -- Brownish 25 1.76 -- -- -- -- -- --
R* - Refusal (SPT N>50), RQD – Rock Quality Designation, qu -Unconfined Compressive Strength

10. Geotechnical Investigation Report- Flyover at ch:0+620
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10
Annexure-II
TABLE-2 SOIL CHARACTERISTICS (BH-2)
Size of Hole: 150mm for Soil Strata & Nx Size for Rock, Period: 18 July2020 to 25 July2020
Depth
from
GL
(m)
Observed
N-
values
Corrected
N
n
Core
Recovery
%
RQD
%
Unconfned
Comp.Stren
gth
(t/m2)
Return Water
Dry
Density
Grain Size Distribution %
Plastic
Characteristics
Shear Strength
Parameters
Colour
Loss
%
Gravel Sand
Silt /
Clay Size
LL PL
C’
kg/cm2 Ф
1.50 34 48 0 0 -- Brownish 30 1.74 14 76 10 NP 0.0 30.0
3.00 R* 50 0 0 -- Brownish 25 1.75 16 73 11 NP 0.0 31.6
4.50 R* 50 0 0 -- Brownish 25 1.75 15 76 9 NP 0.0 33.2
6.00 R* 50 0 0 -- Brownish 25 1.75 17 72 11 NP 0.0 33.2
7.50 R* 50 0 0 -- Brownish 25 1.75 16 72 12 NP 0.0 33.0
9.00 R* 50 0 0 -- Brownish 25 1.76 34 53 13 NP 0.0 33.1
10.50 -- -- 0 0 -- Brownish 25 1.75 -- -- -- -- -- --
12.00 -- -- 0 0 -- Brownish 25 1.76 -- -- -- -- -- --
13.50 -- -- 0 0 -- Brownish 25 1.76 -- -- -- -- -- --
15.00 -- -- 0 0 -- Brownish 25 1.76 -- -- -- -- -- --
R* - Refusal (SPT N>50), RQD – Rock Quality Designation, qu -Unconfined Compressive Strength