PROPOSED CONSTRUCTION OF G+2 … Investigation Report Project No: MSGTPL/SI-3597/16-17 Nov-2016. 1...
Transcript of PROPOSED CONSTRUCTION OF G+2 … Investigation Report Project No: MSGTPL/SI-3597/16-17 Nov-2016. 1...
PROPOSED CONSTRUCTION OF G+2 RESIDENTIAL BUILDING
AT NO:26, BAJANAI KOIL STREET, BHARATHI NAGAR,
SELAIYUR, CHENNAI.
Report on Geotechnical Investigation
Client:
M/s. Alankar Construction,
Chennai.
MARS SYNERGY GEO TECH Pvt Ltd
An ISO 9001: 2015 Certificate Company # 30/25 Drowpathy Amman Koil 1
st Street
Velachery, Chennai-600 042.
Ph : (044) –22452845, Tele Fax: 2245 0281 Mail : [email protected], [email protected],
Web: www.msgeotech.com
Project No: MSGTPL/SI-3597/16-17 Nov-2016.
Geo-Technical Investigation Report
Project No: MSGTPL/SI-3597/16-17 Nov-2016.
Proposed Construction of G+2 Residential Building at Selaiyur
TABLE OF CONTENTS
1.0 INTRODUCTION……………………………………………………………………. 1
1.1 DESCRIPTION OF STRUCTURE………………………………………………… 1
1.2 SOIL INVESTIGATION PROGRAMME …………………………………………. 1
1.3 FIELD SAMPLING……………………………………………….………………… 2
1.4 LABORATORY TESTS…………………………………………………………… 2
1.5 SOIL PROFILE………………………………………………………………………. 2
1.6 GROUND WATER TABLE……………………………………………………….. 3
1.7 DISCUSSION ON FOUNDATION…………………………………………………. 3
1.8 RECOMMENDATIONS……………………………………………………………. 3
2.0 SAFE BEARINGCAPACITY CALCULATIONS.............................................. 4
3.0 SITE PLAN –MSGTPL/SI-3597……………………………………………………. 5
4.0 BORE-LOGS………………………………………………………………………… . 6
5.0 TEST RESULTS…………………………………………………………………….. 8
6.0 NATURAL MOISTURE CONTENT……………………………………………….. 10
7.0 SPECIFIC GRAVITY…………………………………………………………………. 11
8.0 GRAIN SIZE ANALYSIS…………………………………………………………….. 12
Geo-Technical Investigation Report
Project No: MSGTPL/SI-3597/16-17 Nov-2016.
1
Proposed Construction of G+2 Residential Building at Selaiyur
REPORT ON SOIL INVESTIGATION AND RECOMMENDATIONS FOR THE
FOUNDATIONS OF THE PROPOSED CONSTRUCTION OF RESIDENTIAL
BUILDING (G+2) AT SELAIYUR, CHENNAI,
1.0 INTRODUCTION
M/s. Alankar Construction, Chennai are planning to construct the residential building
(G+2) at No:26, Bajanai Koil Street, Bharathi Nagar, Selaiyur, Chennai-600 073,
Tamilnadu, INDIA. M/s. Mars Synergy Geotech Pvt Ltd, Chennai has carried out this
investigation and completed the field work on 08th Nov 2016 according to the instructions
from the owner of the project.
The scope of work includes the following:
� Making two numbers of Standard Soil Investigation bore-holes
� Collecting soil samples at regular depth intervals
� Conducting SPTs at every 1.0m/1.50m depth intervals
� Conducting laboratory tests on samples collected
� Submitting report with laboratory test results and recommendations for
foundations.
1.1 DESCRIPTION OF STRUCTURE
The proposed structure is residential building (G+2). The exact details of columns are
not available at the time of preparation of this report. Assuming an approximate column
spacing of 4 to 5 m c/c considering this the central column load works about 60 to 70
tones for proposed building. These loads are assumed for the purpose of foundation
only and for the structural design, exact loads are to be estimated based on a suitable
structural analysis.
1.2 SOIL INVESTIGATION
The field investigation works were carried out using 1 set of Rotary mechanical drilling
Rig. The following activities, carried out in chronological sequence, comprised the
fieldwork for the project
• Mobilisation of rotary drill rig, water pump, testing tools and accessories.
• Collection of disturbed samples of non-cohesive soils.
• Sampling and logging of the boreholes. Packing, labeling and dispatching the
samples to laboratory.
• Field investigation, tests and laboratory tests conducted as per IS-1892 and IS -2720
Geo-Technical Investigation Report
Project No: MSGTPL/SI-3597/16-17 Nov-2016.
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Proposed Construction of G+2 Residential Building at Selaiyur
1.3 FIELD SAMPLING
Two numbers of standard soil investigation boreholes of 100mm diameter was made at
the locations shown in the figure, MSGTPL/SI-3597 enclosed. Investigations were
conducted up to 5.50 from existing ground level where SPT is more than 50blows. SPTs
were conducted at every 1.0m/1.5m depth intervals and samples were collected for
identification and testing.
1.4 LABORATORY TESTS
The laboratory-testing scheme is so designed to obtain the design parameters for the
foundations. The following parameters are evaluated:
� Type of soil and it's gradation properties
� Specific Gravity
� Natural Moisture Content (NMC)
� Sieve analysis on the coarse grained soil fraction
All the test results are presented in the tabular forms. Comprehensive field information
along with SPT values is presented on separate sheet.
1.5 SOIL PROFILE
Based on visual identification of soil samples and test results (of both field and
laboratory tests), the soil profile arrived. Subsoil is made-up of three distinctive layers
there are
(i) Medium Dense clayey SAND up to -1.50m with SPT’s N=25
(ii) Very Dense moorum -1.50m to -3.50m with SPT’s N=>50
(iii) Soft disintegrated Rock -3.50m to -5.0m with SPT’s N=>100
The soil profile details are presented in the bore-chart.
1.6 GROUND WATER TABLE
At the time of soil investigation (08/11/2016), the ground water table was not
encountered within the site location. However Ground water table in recorded from
nearby open well at (-) 4.0m from existing ground level.
Geo-Technical Investigation Report
Project No: MSGTPL/SI-3597/16-17 Nov-2016.
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Proposed Construction of G+2 Residential Building at Selaiyur
1.7 DISCUSSION ON FOUNDATION
From the sub soil profile and laboratory test data, it can be seen that the soil is medium
dense SAND up to -1.50m followed by very dense moorum up to -3.50m, below this
layer 1.50m thick soft disintegrated rock layer is encountered up to -5.0m from existing
ground level.
Based on soil strata it is ideal to adopt open shallow foundation at -1.50m level,
recommended.
1.8 RECOMMENDATIONS
� Open shallow in the form of isolated column footings/Strip Raft located at a
depth of -1.50m below the existing G.L
� The Safe bearing capacity can be taken of soil at 1.50m below G.L can be taken
as 20T/sq.m., Similarly SBC at 2.0m depth 25T/sq.m can be adopted.
� These footing should rest on 100mm thick of 1:3:6 mat.
� Columns shall be tied in both directions at plinth level.
� All foundation works should be done in dry conditions only.
Note: This recommendation has been given on the assumed loads. The structural engineer
can modify it based on structural analysis on actual size of the building and column details.
Geo-Technical Investigation Report
Project No: MSGTPL/SI-3597/16-17 Nov-2016.
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Proposed Construction of G+2 Residential Building at Selaiyur
2.0 DETERMINATION OF BEARING CAPACITY OF SHALLOW FOUNDATIONS
[Based On IS: 6403-1981]
Footing Size =1.5mx1.5m (Assumed for calculation) Depth of Foundation: 1.50m
Existing Ground level: 0.00M
Ground Water Table level: -0.00M (Due to Heavy Rain Temporary)
Bulk Density (W) of Soil above Footing Base: 1.85
Submerged Density (W') of Soil above Footing Base: 0.85T/Cu.M.
Bulk Density (W) of Soil below Footing Base: 1.85
Shape factor Depth Factor Inclination Factor Sq = 1.00 Dq = 1.17 Iq = 1.000 Sg = 0.80 Dg = 1.17 Ig = 1.000 Water Table Correction Factor w’ = 0.50
Effective surcharge at base level q = 1.275 T/Sq.M.
Ultimate Net B.C. = Qult_n = q*(Nq-1)*Sq*Dq*Iq + 0.5*B*W*Ng*Sg*Dg*Ig*W'
Angle of Internal Friction (phai): 31
Bearing Capacity Factors Nq = 21.38, Ng = 27.53
Thus Qult_n =50.32T/Sq.M. Allowable Bearing Capacity (Qall) = 20.13T/Sq.M. Say 20T/m2
Settlement Calculations as per IS-8009-(Part1) 1998 S= Sc+Si
Sc=5mm
=0.0143x1000=14.30mm S= Sc+Si
S=5+14.30=19.30mm Say=20mm
Total settlements 20.0 mm, It is less than 25mm hence it is safe as per IS 1904-1986.
IEs
pBSi)1(
2µ−
=
mxSi 0143.013.12500
)3.01(5.120
2
=−
=
4.0 BORE-LOGS
Bore Hole No.
Type of Boring
Started on
Ended on
Dep
th (
m)
15 30 45 N
0.0 0.00
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
4.00
65 8722
-
Graphical Representation of SPT
13
25
Type o
f S
am
ple
s
Depth
(m
)
5.00
SP
T
Layer
Thic
kness
Soil Description
2.00
1.00
SPT Details
IS C
lassific
ation
Soil
Pro
file
s
11
Project No: MSGTPL/SI-3597/16-17
Project : Proposed Construction of G+2 Residential Building at Selaiyur
:1
Dia of Boring
:NilG.W.L
:100mm
: Ref. Fig
: 5.0m
Location
Soil Drilled
3.00
:Rotary
:08/11/2016
:08/11/2016
SP
TS
PT
SP
TS
PT
148
- -
>100---
50 Blows for 10cm
>100
2.50
2.00
1.00
GP
GP
SCMedium Dense Brownish
Clayey SAND
Brownish Moorum
Soft Disintegrated Rock
0 10
20
30
40
50
70
60
80
90 10
0
7.5
8.0
8.5
9.0
9.5
10.0
Soil Profile BH-1 Location
Borehole Terminated at 5.0m Below Ground Level.
6
Bore Hole No.
Type of Boring
Started on
Ended on
Dep
th (
m)
15 30 45 N
0.0 0.00
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
4.5
5.0
5.5
6.0
6.5
7.0
7.5
52
>100-
SC
--3.50
15
: Ref. Fig
: 3.5m
Location
Soil Drilled
SP
TS
PT
SP
T
SPT Details
IS C
lassific
ation
Soil
Pro
file
s
40
Very Dense Brownish Clayey
SAND
:Rotary
:08/11/2016
:08/11/2016
Project No: MSGTPL/SI-3597/16-17
Project : Proposed Construction of G+2 Residential Building at Selaiyur
:2
Dia of Boring
:NilG.W.L
:100mm
Graphical Representation of SPT
-
92
Type o
f S
am
ple
s
Depth
(m
)
2.00
1.00
Layer
Thic
kness
Soil Description
1.00
- >100-
Soft Diisntegrtaed Rock GP
2.50
0 10
20
30
40
50
70
60
80
90 10
0
7.5
8.0
8.5
9.0
9.5
10.0
Borehole Terminated at 3.5m Below Ground Level.
Soil Profile BH-2 Location
7
5.0 TEST RESULTS
Project No: MSGTPL/SI-3597/16-17
NM
C
WL
WP
I P Ic
Fre
eS
we
ll
Gra
ve
l
Co
ars
e S
an
d
Me
diu
m S
an
d
Fin
e S
an
d
Sil
t &
Cla
y
0.00
25 1.00 14 2.67 7 5 25 24 39
87 2.00 7 2.68 12 9 27 24 28
>100 3.00 7 2.67 43 8 18 17 14
>100 4.00
>100 5.00
2.00
Medium Dense Brownish
Clayey SAND
Brownish Moorum
IS C
las
sif
ica
tio
n
GP
GP
SC
SUMMARY OF TEST RESULTS
La
ye
r T
hic
kn
es
s
Grain Size Analysis (%)
Soft Disintegrated Rock
1.00
2.00
Sp
ec
ific
Gra
vit
y
Project : Proposed Construction of G+2 Residential Building at Selaiyur
So
il D
es
cri
pti
on
De
pth
(m
)
N' V
alu
e
1BH No Termination Depth: -: 5.0mGround Water Level:Nil
Index Properties (%)
8
Project No: MSGTPL/SI-3597/16-17
NM
C
WL
WP
I P Ic
Fre
eS
we
ll
Gra
ve
l
Co
ars
e S
an
d
Me
diu
m S
an
d
Fin
e S
an
d
Sil
t &
Cla
y
0.00
92 1.00 8 2.68 1 2 32 32 33
>100 2.00
>100 3.50
Termination Depth: -: 3.5mGround Water Level:Nil
Index Properties (%)
IS C
las
sif
ica
tio
n
Very Dense Brownish
Clayey SAND
2.50
1.00 SC
GPSoft Diisntegrtaed Rock
SUMMARY OF TEST RESULTS
La
ye
r T
hic
kn
es
s
Grain Size Analysis (%)
Sp
ec
ific
Gra
vit
y
Project : Proposed Construction of G+2 Residential Building at Selaiyur
So
il D
es
cri
pti
on
De
pth
(m
)
N' V
alu
e
1BH No
9
6.0 NATURAL MOISTURE CONTENT
Project No: MSGTPL/SI-3597/16-17
Project : Proposed Construction of G+2 Residential Building at Selaiyur
Method: IS-2720 P-2
BH.No/ Pit no
Natural Moisture Content Data Sheet
1 1 1 2BH.No/ Pit no
Depth (m)
Tare No 13 2 164 8 219 24 65 237
Wt of Tare (gr) 29.80 28.36 30.61 29.23 31.53 31.35 28.45 29.10
Tare + Soil (gr) 58.77 55.36 65.37 66.97 50.86 53.48 56.44 54.99
Tare+Dry soil (gr) 55.12 51.93 63.00 64.31 49.52 51.96 54.49 53.00
Wt of Water (gr) 3.65 3.43 2.37 2.66 1.34 1.52 1.95 1.99
Wt Dry soil (gr) 25.32 23.57 32.39 35.08 17.99 20.61 26.04 23.90
Water Content (%) 14.42 14.55 7.32 7.58 7.45 7.38 7.49 8.33
Average Water
Content (%) 8
1.0
14 7 7
3.02.01.0
1 1 1 2
10
7.0 SPECIFIC GRAVITY
Project No: MSGTPL/SI-3597/16-17
BH.No 1 BH.No 1
Depth(m) 1.0 Depth(m) 2.0
Pycnometer number 46 43 Pycnometer number 71 72
Weight of bottle w1 g 32.7700 32.2300 Weight of bottle w1 g 36.2900 34.0700
Weight of bottle + soil w2 g 54.4200 54.2200 Weight of bottle + soil w2 g 59.2500 56.5000
Weight of bottle + soil + water w3 g 101.3500 101.2500 Weight of bottle + soil + water w3 g 101.9700 99.9000
Weight of bottle full of water w4 g 87.8300 87.4900 Weight of bottle full of water w4 g 87.5500 85.8700
w2-w1 g 21.6500 21.9900 w2-w1 g 22.9600 22.4300
w2-w1
(w4-w1)-(w3-w2)2.66298 2.67193
w2-w1
(w4-w1)-(w3-w2)2.68852 2.67024
2.67 2.68
Project : Proposed Construction of G+2 Residential Building at Selaiyur
Specific gravity
Weight of soil
SPECIFIC GRAVITY TEST
Average value Gs Average value Gs
Weight of soil
Specific gravity
11
Project No: MSGTPL/SI-3597/16-17
BH.No 1 BH.No 2
Depth(m) 3.0 Depth(m) 1.0
Pycnometer number 19 25 Pycnometer number 32 38
Weight of bottle w1 g 34.6800 38.0800 Weight of bottle w1 g 46.3100 40.6400
Weight of bottle + soil w2 g 53.2400 55.6300 Weight of bottle + soil w2 g 68.1100 61.9100
Weight of bottle + soil + water w3 g 93.6700 92.8500 Weight of bottle + soil + water w3 g 110.5000 107.6600
Weight of bottle full of water w4 g 82.0700 81.8600 Weight of bottle full of water w4 g 96.8300 94.3200
w2-w1 g 18.5600 17.5500 w2-w1 g 21.8000 21.2700
w2-w1
(w4-w1)-(w3-w2)2.66667 2.67530
w2-w1
(w4-w1)-(w3-w2)2.68143 2.68222
2.67 2.68
SPECIFIC GRAVITY TEST
Average value Gs Average value Gs
Weight of soil
Specific gravity
Project : Proposed Construction of G+2 Residential Building at Selaiyur
Specific gravity
Weight of soil
12
8.0 GRAIN SIZE ANALYSIS
BH 1
Depth
% Soil
retained
Cumulative %
FinerAverage Sieve
PSR % F % size (mm)(1) (2) (3)
6.74 93.27 4.750
5.28 87.99 3.375
15.28 72.71 1.500
5.10 67.61 0.800
4.86 62.75 0.513
8.23 54.53 0.319
7.23 47.30 0.181
8.33 38.97 0.113
Average Particle Diameter = 0.8767
BH 1
Depth
% Soil
retained
Cumulative %
FinerAverage Sieve
PSR % F % size (mm)(1) (2) (3)
12.30 87.70 4.750
8.89 78.81 3.375
16.52 62.30 1.500
4.81 57.49 0.800
5.37 52.12 0.513
8.99 43.13 0.319
5.45 37.68 0.181
9.21 28.47 0.113
1.2987
Gravel
Fine Medium Coarse Fine Medium Coarse Fine
% Particle Size 2.0 %
7 Gravel 12
5 Coarse Sand 9
25 0.757 Medium Sand 27
24 Fine Sand 24
39 Silt & Clay 28
Silt
0.212
0.150
9
8
8
9
2.0m
2
1
1.0m
S.No.
2.000
Clay
Average Particle Diameter =
0.600
passing 0.075
0.425
7
6
5
4
S.No.
6
7
Sieve Analysis Test
1
2
3
Product of
Columns(1) x (3)31.99
24.77
4
5
Sieve Aperture size used
(mm)
4.750
3
Sand
124.679
0.99
1.04
2.75
2.86
2.000
17.82
22.92
4.08
2.62
1.31
0.94
Product of
84.163
(1) x (3)
0.150
0.075
4.750
passing 0.075
Sieve Aperture size used
(mm)
3.85
1.000
58.43
30.00
Medium Sand
Fine Sand
0.075
0.087
0.809
Particle Size
Silt & Clay
Project : Proposed Construction of G+2 Residential Building at Selaiyur
Project No: MSGTPL/SI-3597/16-17
Gravel
Coarse Sand
1.0
1.000
0.600
0.425
0.212
2.49
0
10
20
30
40
50
60
70
80
90
100
0.001 0.010 0.100 1.000 10.000
Particle size [mm]I Depth II Depth
Cum
ula
tive
P
erc
enta
ge F
iner
D10 =D30 =D60 =
D10 =D30 =D60 =
Depth = Depth =
Cu =
Cc =
Cu =
Cc =
13
BH 1
Depth
% Soil
retained
Cumulative %
FinerAverage Sieve
PSR % F % size (mm)(1) (2) (3)
42.89 57.11 4.750
7.89 49.22 3.375
9.51 39.71 1.500
3.66 36.05 0.800
4.99 31.06 0.513
7.45 23.61 0.319
3.18 20.43 0.181
6.84 13.59 0.113
Average Particle Diameter = 2.6440
BH 2
Depth
% Soil
retained
Cumulative %
FinerAverage Sieve
PSR % F % size (mm)(1) (2) (3)
1.00 99.00 4.750
2.39 96.61 3.375
17.42 79.19 1.500
7.59 71.60 0.800
7.35 64.25 0.513
15.67 48.58 0.319
8.51 40.07 0.181
7.95 32.12 0.113
0.5856
Gravel
Fine Medium Coarse Fine Medium Coarse Fine
% Particle Size 1.0 %
43 Gravel 1
8 0.395 Coarse Sand 2
18 8.610 Medium Sand 32
17 Fine Sand 32
14 Silt & Clay 33
2.56
Silt & Clay
Project : Proposed Construction of G+2 Residential Building at Selaiyur
Project No: MSGTPL/SI-3597/16-17
Gravel
Coarse Sand
3.0
1.000
0.600
0.425
0.212
8.08
Medium Sand
Fine Sand
0.075
0.367
Particle Size
253.825
0.150
0.075
4.750
passing 0.075
Sieve Aperture size used
(mm)
6.07
1.000
4.75
Sand
56.220
1.54
0.89
2.000
26.63
14.27
2.93
2.37
0.58
3.77
4.99
(1) x (3)
Product of
Columns(1) x (3)203.73
26.13
0.77
Product of
4
5
5
4
S.No.
6
7
Sieve Analysis Test
1
2
3
Sieve Aperture size used
(mm)
4.750
3.0m
S.No.
2.000
Clay
Average Particle Diameter =
0.600
passing 0.075
0.425
7
6
Silt
0.212
0.150
9
8
8
9
1.0m
2
1
3
0
10
20
30
40
50
60
70
80
90
100
0.001 0.010 0.100 1.000 10.000
Particle size [mm]I Depth II Depth
Cum
ula
tive
P
erc
enta
ge F
iner
D10 =D30 =D60 =
D10 =D30 =D60 =
Depth = Depth =
Cu =
Cc =
Cu =
Cc =
14