MARS SYNERGY GEO TECH Pvt Ltd An ISO 9001: 2015 Certificate Company # 30/25 Drowpathy Amman Koil 1 st Street Velachery, Chennai

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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.

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 Ph : (044) , Tele Fax: Mail : info@msgeotech.com, projects@msgeotech.com, Web: Nov2016.

2 Proposed Construction of G+2 Residential Building at Selaiyur TABLE OF CONTENTS 1.0 INTRODUCTION DESCRIPTION OF STRUCTURE SOIL INVESTIGATION PROGRAMME FIELD SAMPLING LABORATORY TESTS SOIL PROFILE GROUND WATER TABLE DISCUSSION ON FOUNDATION RECOMMENDATIONS SAFE BEARINGCAPACITY CALCULATIONS SITE PLAN MSGTPL/SI BORELOGS TEST RESULTS NATURAL MOISTURE CONTENT SPECIFIC GRAVITY GRAIN SIZE ANALYSIS.. 12 GeoTechnical Investigation Report Nov2016.

3 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 , Tamilnadu, INDIA. M/s. Mars Synergy Geotech Pvt Ltd, Chennai has carried out this investigation and completed the field work on 08 th 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 boreholes 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 noncohesive soils. Sampling and logging of the boreholes. Packing, labeling and dispatching the samples to laboratory. Field investigation, tests and laboratory tests conducted as per IS1892 and IS 2720 GeoTechnical Investigation Report 1 Nov2016.

4 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/SI3597 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 laboratorytesting 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 madeup 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 borechart. 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. GeoTechnical Investigation Report 2 Nov2016.

5 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. GeoTechnical Investigation Report 3 Nov2016.

6 Proposed Construction of G+2 Residential Building at Selaiyur 2.0 DETERMINATION OF BEARING CAPACITY OF SHALLOW FOUNDATIONS [Based On IS: ] 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 = Sg = 0.80 Dg = 1.17 Ig = Water Table Correction Factor w = 0.50 Effective surcharge at base level q = T/Sq.M. Ultimate Net B.C. = Qult_n = q*(nq1)*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 = Thus Qult_n =50.32T/Sq.M. Allowable Bearing Capacity (Qall) = 20.13T/Sq.M. Say 20T/m 2 Settlement Calculations as per IS8009(Part1) 1998 S= Sc+Si Sc=5mm 2 (1 µ ) Si = pb I Es 2 (1 0.3 ) Si = 20x = m 2500 S= Sc+Si S= =19.30mm =0.0143x1000=14.30mm Say=20mm Total settlements 20.0 mm, It is less than 25mm hence it is safe as per IS GeoTechnical Investigation Report 4 Nov2016.

8 4.0 BORELOGS Bore Hole No. :1 Type of Boring :Rotary Started on :08/11/2016 Ended on :08/11/2016 Depth (m) Medium Dense Brownish 0.5 SC Clayey SAND Layer Thickness Soil Profiles Soil Description Brownish Moorum Soft Disintegrated Rock IS Classification GP GP Depth (m) SPT Details N Blows for 10cm >100 >100 Soil Profile BH1 Location Borehole Terminated at 5.0m Below Ground Level. 0 G.W.L :Nil Dia of Boring :100mm Location : Ref. Fig Soil Drilled : 5.0m Graphical Representation of SPT Type of Samples SPT SPT SPT SPT SPT 6

9 Bore Hole No. :2 Type of Boring :Rotary Started on :08/11/2016 Ended on :08/11/2016 Depth (m) Very Dense Brownish Clayey 0.5 SC SAND Layer Thickness 2.50 Soil Profiles Soil Description Soft Diisntegrtaed Rock IS Classification GP Depth (m) SPT Details N >100 Soil Profile BH2 Location Borehole Terminated at 3.5m Below Ground Level. >100 0 G.W.L Dia of Boring :100mm Location : Ref. Fig Soil Drilled :Nil : 3.5m Graphical Representation of SPT Type of Samples SPT SPT SPT 7

10 5.0 TEST RESULTS BH No 1 Ground Water Level:Nil Termination Depth: : 5.0m SUMMARY OF TEST RESULTS Index Properties (%) Grain Size Analysis (%) N' Value Layer Thickness Depth (m) Soil Description IS Classification NMC W L W P I P Ic FreeSwell Specific Gravity Gravel Coarse Sand Medium Sand Fine Sand Silt & Clay 0.00 Medium Dense Brownish 1.00 SC Clayey SAND Brownish Moorum GP > > > Soft Disintegrated Rock GP 8

11 BH No 1 Ground Water Level:Nil SUMMARY OF TEST RESULTS Index Properties (%) Termination Depth: : 3.5m Grain Size Analysis (%) N' Value Layer Thickness Depth (m) Soil Description IS Classification NMC W L W P I P Ic FreeSwell Specific Gravity Gravel Coarse Sand Medium Sand Fine Sand Silt & Clay 0.00 Very Dense Brownish 1.00 SC Clayey SAND > > Soft Diisntegrtaed Rock GP 9

12 6.0 NATURAL MOISTURE CONTENT Method: IS2720 P2 BH.No/ Pit no Depth (m) Natural Moisture Content Data Sheet Tare No Wt of Tare (gr) Tare + Soil (gr) Tare+Dry soil (gr) Wt of Water (gr) Wt Dry soil (gr) Water Content (%) Average Water Content (%)

13 7.0 SPECIFIC GRAVITY SPECIFIC GRAVITY TEST BH.No 1 BH.No 1 Depth(m) 1.0 Depth(m) 2.0 Pycnometer number Pycnometer number Weight of bottle w 1 g Weight of bottle w 1 g Weight of bottle + soil w 2 g Weight of bottle + soil w 2 g Weight of bottle + soil + water w 3 g Weight of bottle + soil + water w 3 g Weight of bottle full of water w 4 g Weight of bottle full of water w 4 g Weight of soil w 2 w 1 g Weight of soil w 2 w 1 g Specific gravity w2w1 (w4w1)(w3w2) Specific gravity w2w1 (w4w1)(w3w2) Average value G s 2.67 Average value G s

SPECIFIC GRAVITY TEST 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 w 1 g 34.6800 38.0800 Weight of bottle w 1 g 46.3100 40.

14 SPECIFIC GRAVITY TEST BH.No 1 BH.No 2 Depth(m) 3.0 Depth(m) 1.0 Pycnometer number Pycnometer number Weight of bottle w 1 g Weight of bottle w 1 g Weight of bottle + soil w 2 g Weight of bottle + soil w 2 g Weight of bottle + soil + water w 3 g Weight of bottle + soil + water w 3 g Weight of bottle full of water w 4 g Weight of bottle full of water w 4 g Weight of soil w 2 w 1 g Weight of soil w 2 w 1 g Specific gravity w2w1 (w4w1)(w3w2) Specific gravity w2w1 (w4w1)(w3w2) Average value G s 2.67 Average value G s

15 8.0 GRAIN SIZE ANALYSIS BH 1 Sieve Analysis Test Depth 1.0m S.No Sieve Aperture size used (mm) passing Average Particle Diameter = % Soil Cumulative % retained Finer Average Sieve PSR % F % size (mm) (1) (2) (3) Product of Columns (1) x (3) BH 1 Depth 2.0m S.No. Sieve Aperture size used (mm) passing Average Particle Diameter = % Soil Cumulative % retained Finer Average Sieve size (mm) (2) (3) PSR % (1) F % Product of (1) x (3) Clay Silt Sand Gravel Fine Medium Coarse Fine Medium Coarse Fine Cumulative Percentage Finer Particle size [mm] I Depth II Depth Depth = 1.0 % Particle Size Depth = 2.0 % Gravel 7 D 10 = Gravel 12 Coarse Sand 5 D 30 = Coarse Sand 9 D Medium Sand = Medium Sand 27 Fine Sand 24 C u = Fine Sand 24 Silt & Clay 39 C c = Silt & Clay 28 Particle Size D 10 = D 30 = D 60 = C u = C c = 13

BH 1 Sieve Analysis Test Depth 3.0m S.No. 1 2 3 4 5 6 7 8 9 Sieve Aperture size used (mm) 4.750 2.000 1.000 0.600 0.425 0.212 0.150 0.075 passing 0.075 Average Particle Diameter = 2.

16 BH 1 Sieve Analysis Test Depth 3.0m S.No Sieve Aperture size used (mm) passing Average Particle Diameter = % Soil Cumulative % retained Finer Average Sieve PSR % F % size (mm) (1) (2) (3) Product of Columns (1) x (3) BH 2 Depth 1.0m S.No. Sieve Aperture size used (mm) passing Average Particle Diameter = % Soil Cumulative % retained Finer Average Sieve size (mm) (2) (3) PSR % (1) F % Product of (1) x (3) Clay Silt Sand Gravel Fine Medium Coarse Fine Medium Coarse Fine Cumulative Percentage Finer Particle size [mm] I Depth II Depth Depth = 3.0 % Particle Size Depth = 1.0 % Gravel 43 D 10 = Gravel 1 Coarse Sand 8 D 30 = Coarse Sand 2 D Medium Sand = Medium Sand 32 Fine Sand 17 C u = Fine Sand 32 Silt & Clay 14 C c = Silt & Clay 33 Particle Size D 10 = D 30 = D 60 = C u = C c = 14

CEEN Geotechnical Engineering

CEEN Geotechnical Engineering CEEN 3160 - Geotechnical Engineering Lab Report 1 Soil Classification prepared by Student Name 1 Student Name 2 Student Name 3 Student Name 4 Tuesday Lab Time 9:30 10:45 Lab Team 1 Submission Date INTRODUCTION