Arun Soil Lab Pvt.Ltd.
Geotech and Material Consultants
Geotech and Material Consultants
Ensure and Assure safety of the structures
For a better and safe place to live and work with strong foundation
Quality Consiousness is Our Core Concept
For a better and safe place to live and work with strong foundation
Quality Consiousness is Our Core Concept
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We have completed 20 years of our existence.
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We are now having rock exploration facilities also.
Geotech Investigation
Geotechnical investigations are performed by geotechnical engineers to obtain information on the physical properties of soil and rock at the site to design the foundations for proposed structures based on the subsurface conditions obtained. Geotechnical investigations generally include surface and subsurface exploration of a site. Sometimes, geophysical methods are used to obtain data about sites. Subsurface exploration usually involves soil sampling and laboratory tests of the soil samples retrieved.
Tests on soil for Civil Engineering Structures
Field Tests
(1) Boring and Sampling of soil as per IS 1892 : 1979
(2) Standard Penetration Test as per IS 2131 : 1981
(3) Dynamic Cone Penetrometer Test as per IS 4968 (Part 2) : 1976
(4) Plate Load Test as per IS 1888 : 1982
(5) Electrical Resistivity Test as per IS: 3043-1996)
(2) Standard Penetration Test as per IS 2131 : 1981
(3) Dynamic Cone Penetrometer Test as per IS 4968 (Part 2) : 1976
(4) Plate Load Test as per IS 1888 : 1982
(5) Electrical Resistivity Test as per IS: 3043-1996)
Lab Tests
(1) Preparation of soil sample
(2) Determination of moisture content and bulk density
(3) Specific Gravity
(4) Particle Size Analysis by Mechanical & Sedimentation method
(5) Atterberg Limits including Liquid Limit, Plastic Limit and Shrinkage Limit
(6) Shear Characteristics like Unconfined Compressive Strength, Triaxial Compression Test and Direct Shear Test
(7) Consolidation Test , Swelling Pressure and Differential Free Swell Index
(8) Permeability Test
(2) Determination of moisture content and bulk density
(3) Specific Gravity
(4) Particle Size Analysis by Mechanical & Sedimentation method
(5) Atterberg Limits including Liquid Limit, Plastic Limit and Shrinkage Limit
(6) Shear Characteristics like Unconfined Compressive Strength, Triaxial Compression Test and Direct Shear Test
(7) Consolidation Test , Swelling Pressure and Differential Free Swell Index
(8) Permeability Test
Preparation of Report
(1) Soil classification and identification
(2) Bearing Capacity and Settlement Calculations and suggesting conclusions for the type of Foundation to be provided for a given Structure
(2) Bearing Capacity and Settlement Calculations and suggesting conclusions for the type of Foundation to be provided for a given Structure
Tests on soil for Roads/Airports
Field Tests
(1) Field Density and Moisture
(2) Benkelman Beam Deflection Survey
(3) TRL Dynamic Cone Penetration Test
(2) Benkelman Beam Deflection Survey
(3) TRL Dynamic Cone Penetration Test
Lab Tests
(1) Proctor Test for Optimum Moisture Content and Maximum Dry Density
(2) CBR Test
(2) CBR Test
Soil Classification as per IS: 1498-1970
Classification of soils is divided in to three parts -
(1) Coarse grained soils in which more than half of the total material by weight is larger than 75 micron IS sieve size.
(2) Fine grained soils in which more than half of the total material by weight is smaller than 75 micron IS sieve size.
(3) Highly Organic Soils and other miscellaneous soil materials such as peat, and particles of decomposed vegetation.
(2) Fine grained soils in which more than half of the total material by weight is smaller than 75 micron IS sieve size.
(3) Highly Organic Soils and other miscellaneous soil materials such as peat, and particles of decomposed vegetation.
Coarse grained soils
1. Boulder - > 300 mm
2. Cobble - 300 mm to 75 mm
3. Gravel - 75 mm - 4.75 mm
- Coarse - 75 mm to 20 mm
- Fine - 20 mm to 4.75 mm
4. Sand - 4.75 mm to 75 micron
- Coarse 4.75mm to 2.00 mm
- Medium - 2.00 mm to 0.425 mm
- Fine - 0.425 mm to 0.075 mm
2. Cobble - 300 mm to 75 mm
3. Gravel - 75 mm - 4.75 mm
- Coarse - 75 mm to 20 mm
- Fine - 20 mm to 4.75 mm
4. Sand - 4.75 mm to 75 micron
- Coarse 4.75mm to 2.00 mm
- Medium - 2.00 mm to 0.425 mm
- Fine - 0.425 mm to 0.075 mm
Fine grained soils
1. Silt - That fine grained portion of soil which exhibits little or no plasticity and has little or no strength when air dried with grain size from 0.075 mm to 0.002 mm.
2. Clay - Particles finer than 0.002 mm possessing plastic properties with moderate to wide range of water content.
3. Organic Matter - It is in various sizes and stages of decomposition
- Coarse - 75 micron to 7.50 micron
- Fine - 7.50 micron to 2.00 micron
( *Note:- Symbols for Gravel, Sand, Silt, Clay and Organic matter are G, S, M, C and O respectively. )
2. Clay - Particles finer than 0.002 mm possessing plastic properties with moderate to wide range of water content.
3. Organic Matter - It is in various sizes and stages of decomposition
- Coarse - 75 micron to 7.50 micron
- Fine - 7.50 micron to 2.00 micron
( *Note:- Symbols for Gravel, Sand, Silt, Clay and Organic matter are G, S, M, C and O respectively. )
Specific Gravity as per IS: 2720 (Part 3/Sec 1 & 2) -1987
This is the ratio of the mass of unit volume of soil at a stated temperature to the mass of the same volume of gas free distilled water at a stated temperature.
Grain Size Analysis as per IS: 2720 (Part 4) -1985
Grain size analysis express quantitatively the proportions by mass of the various size of particles present in the soil.
Two methods are given for finding the distribution of grain size larger than 75 micron IS Sieve; the first method wet sieving shall be applicable only to soils which do not have an appreciable amount of clay.
For the determination of distribution of grain sizes smaller than 75 microns, the pipette method is given as the standard method. This method shall be not applicable if less than 10 percent of material passes the 75 micron IS sieve.
- Pipette Method.
- Hydrometer Method.
The methods are not applicable if less than 10 percent material passes the 75 micron sieve.
Two methods are given for finding the distribution of grain size larger than 75 micron IS Sieve; the first method wet sieving shall be applicable only to soils which do not have an appreciable amount of clay.
For the determination of distribution of grain sizes smaller than 75 microns, the pipette method is given as the standard method. This method shall be not applicable if less than 10 percent of material passes the 75 micron IS sieve.
- Pipette Method.
- Hydrometer Method.
The methods are not applicable if less than 10 percent material passes the 75 micron sieve.
Atterberg Limits as per IS: 2720 (Part 5)-1985
(1) Liquid Limit
The water content, expressed as a percentage of the weight of oven dry soil, at the boundary between liquid and plastic states of consistency of soil.
It is the water content at which a pat of soil, cut by a groove of standard dimensions, will flow together for a distance of 12 mm under the impact of 25 blows in a standard liquid limit test apparatus.
(2) Plastic Limit
The water content, expressed as a percentage of the weight of oven dry soil, at the boundary between the plastic and the semi-solid states of consistency of soil. Plastic limit is the water content of soil mass weighing about 8 gms rolled into a thread of diameter nearly 3 mm corresponding to a stage when it begins to crumble.
(3) Shrinkage Limit as per IS: 2720 (Part 6)-1972
The maximum water content expressed as percentage of oven-dry weight at which any further reduction in water content will not cause a decrease in volume of the soil mass.
Triaxial Compression Test as per IS: 2720 (Part 11)-1971 for determining shear strength parameters
A cylindrical specimen of soil encased in an impervious membrane is subjected to a constant confining pressure and then loaded axially @ 1.25 mm per minute to failure without change in total water content in the specimen.
The test is limited to specimen in the form of the right cylinder of nominal diameter 38 mm and height equal to twice the nominal diameter. The ratio of diameter of the specimen to maximum size of particle in the soil should not be less than 5.
The test is limited to specimen in the form of the right cylinder of nominal diameter 38 mm and height equal to twice the nominal diameter. The ratio of diameter of the specimen to maximum size of particle in the soil should not be less than 5.
Direct Shear Test as per IS: 2720 (Part 13)-1986
A shear test in which soil under an applied normal load is stressed to failure by one section of the soil container (shear box) relative to the other section.
The methods for determination of shear strength of soil with a maximum particle size of 4.75mm are in undrained, consolidated undrained and consolidated drained condition.
The methods for determination of shear strength of soil with a maximum particle size of 4.75mm are in undrained, consolidated undrained and consolidated drained condition.
Consolidation Test as per IS: 2720 (Part 15)-1986
A test in which the specimen is laterally confined in a ring and is compressed between porous plates in fully saturated condition. The gradual reduction in volume of soil mass on application of compressive stress is due to expulsion of water from the pores. The height of the ring shall not be less than 20mm. with diameter to height ratio of about 3. Further the specimen height shall be not less than 10 times the maximum particle size.
Determination of pH Value as per IS: 2720 (Part 26)-1987
The reading is taken directly by pH meter with glass electrode and a calomel reference electrode.
Determination of Calcium Carbonate as per IS: 2720 (Part 23)-1987
Determination of Total Soluble Sulphates as per IS: 2720 (Part 27)-1987
Determination of Organic Matter as per IS: 2720 (Part 22)-1978
Permeability Test as per IS: 2720 (Part 17)-1986
The knowledge of the permeability is essential in the solution of many engineering problems involving flow of water through soils such as:
(1) Dewatering and drainage of excavations, back-fills and sub-grades.
(2) Determining yield of water bearing strata.
(3) Assessing seepage through the body of earth dams.
(4) Computing losses from canals.
(2) Determining yield of water bearing strata.
(3) Assessing seepage through the body of earth dams.
(4) Computing losses from canals.
Electrical Resistivity Test as per IS: 3043-1987 (Reaffirmed 1996)
Introduction
To design the most economical and technically sound grounding system for electric sub-station, it is necessary to obtain accurate data on the soil resistivity and on its variation at the site. Variation of the resistivity of the soil with depth is more predominant as compared to the variation with horizontal distance.
Resistivity measurements at the site reveal whether the soil is homogeneous or non-uniform the resistivity of earth varies overall wide range depending on its moisture content, stratification and composition of earth layers. It is therefore, advisable to conduct earth resistivity tests during the dry season in order to get conservative result.
Resistivity measurements at the site reveal whether the soil is homogeneous or non-uniform the resistivity of earth varies overall wide range depending on its moisture content, stratification and composition of earth layers. It is therefore, advisable to conduct earth resistivity tests during the dry season in order to get conservative result.
Principle of test
Wenner's four electrode method is recommended for this type of field investigation. In this method four electrodes are driven into the earth along a straight line at equal intervals.
Earth testers normally used for these tests comprise the current source and meter in a single instrument and directly read the resistance.
Earth testers normally used for these tests comprise the current source and meter in a single instrument and directly read the resistance.
Proctor Compaction Test (Moisture-Density Test) as per IS: 2720 (Part7)-1980 using light compaction and IS: 2720 (Part 8)-1983 using heavy compaction
Soil at known water content is placed in a specified rammer in to a mould of given dimensions, subjected to a compactive effort of controlled magnitude and the resulting unit weight determination. The procedure is repeated for varying Water Content and Dry Unit Weight.
California Bearing Ratio (CBR) as per IS: 2720 (Part 16)-1979
The Ratio of the force per unit area to penetrate a soil mass with circular plunger of 50 mm diameter @ 1.25 mm/min to that required for corresponding penetration of a standard material.
CBR = [PT / PS] x 100
PT = Corrected unit (or total) test load corresponding to the chosen penetration from the load penetration curve (fig. 2 of chapter IS: 2720 (Part 16)-1979 Method of test for soils: Part 16 Laboratory Determination of CBR (first revision) in Compendium of Indian Standards on Soil Engineering Part 1)
PS = unit (or total) standard load for the same depth of penetration as for PS taken from table below.
CBR = [PT / PS] x 100
PT = Corrected unit (or total) test load corresponding to the chosen penetration from the load penetration curve (fig. 2 of chapter IS: 2720 (Part 16)-1979 Method of test for soils: Part 16 Laboratory Determination of CBR (first revision) in Compendium of Indian Standards on Soil Engineering Part 1)
PS = unit (or total) standard load for the same depth of penetration as for PS taken from table below.
Other IS Code References in Geotech Investigation
(1) IS: 5329 (Part I) - 1985 for In-situ Permeability test (in Overburden)
(2) IS: 5329 (Part II) - 1985 for In-situ Permeability test (in Bed Rock)
(3) IS: 6403-1981 for determination of Bearing Capacity
(4) IS: 8009(Part I) - 1976 for calculation of settlement of shallow foundations
(5) IS: 8009(Part II) - 1980 for calculation of settlement of deep foundations
(6) IS: 1904-1986 for permissible maximum settlement, differential settlement and angular distortion
(7) IS: 1080-1985 Design & Construction of shallow foundation in soils (other than raft,Ring & Shell)
(8) IS: 2950 (Part I) - 1981 Design & Construction of Raft foundation
(9) IS: 11089-1984 Design & Construction of Ring foundation
(10) IS: 1893-Part 1: 2002 Criteria for Earthquake resistant design of structures
(11) IS: 3043-1987 for Electrical Resistivity Test
(2) IS: 5329 (Part II) - 1985 for In-situ Permeability test (in Bed Rock)
(3) IS: 6403-1981 for determination of Bearing Capacity
(4) IS: 8009(Part I) - 1976 for calculation of settlement of shallow foundations
(5) IS: 8009(Part II) - 1980 for calculation of settlement of deep foundations
(6) IS: 1904-1986 for permissible maximum settlement, differential settlement and angular distortion
(7) IS: 1080-1985 Design & Construction of shallow foundation in soils (other than raft,Ring & Shell)
(8) IS: 2950 (Part I) - 1981 Design & Construction of Raft foundation
(9) IS: 11089-1984 Design & Construction of Ring foundation
(10) IS: 1893-Part 1: 2002 Criteria for Earthquake resistant design of structures
(11) IS: 3043-1987 for Electrical Resistivity Test
Rock Drilling ( Rotary Core Drilling - NX size - using diamond & TC Bits )
Diamond core drilling utilizes an annular diamond-impregnated drill bit attached to the end of hollow drill rods to cut a cylindrical core of solid rock. The diamonds used are fine to microfine industrial grade diamonds. They are set within a matrix of varying hardness, from brass to high-grade steel. Matrix hardness, diamond size and dosing can be varied according to the rock which must be cut. Holes within the bit allow water to be delivered to the cutting face. This provides three essential functions - lubrication, cooling, and removal of drill cuttings from the hole.
At Field
Boring and Sampling of rock cores for calculating RQD.
At Laboratory
(a) Unconfined Compressive Strength
(b) Tensile Strength
(c) Quantitative Description including Core recovery and rock quality
(d) Quantitative Description of rock mass
(e) Water content, Porosity, Density, etc.
(f) Strength
(b) Tensile Strength
(c) Quantitative Description including Core recovery and rock quality
(d) Quantitative Description of rock mass
(e) Water content, Porosity, Density, etc.
(f) Strength
IS Code References
1.IS : 5313-1980 Guide for core drilling of formations
2.IS: 9143-1979 for Unconfined Compressive Strength of rock
3.IS: 9179-1979 for preparation of rock specimen for laboratory testing
4.IS: 10082-1981 for Tensile Strength by indirect tests on rock specimens
5.IS: 11315-1987 for Quantitative Description of rock mass
6.IS: 13365 (Part 1)-1998 for Rock Mass Rating (RMR)
7.IS: 13365 (Part 2)-1992 for Rock Mass Quality (RQD)
8.IS: 13030-1991 for laboratory determination of Water content, Porosity, Density, etc.
9.IS: 13047-1991 for determination of Strength of rock materials in Triaxial Compression
2.IS: 9143-1979 for Unconfined Compressive Strength of rock
3.IS: 9179-1979 for preparation of rock specimen for laboratory testing
4.IS: 10082-1981 for Tensile Strength by indirect tests on rock specimens
5.IS: 11315-1987 for Quantitative Description of rock mass
6.IS: 13365 (Part 1)-1998 for Rock Mass Rating (RMR)
7.IS: 13365 (Part 2)-1992 for Rock Mass Quality (RQD)
8.IS: 13030-1991 for laboratory determination of Water content, Porosity, Density, etc.
9.IS: 13047-1991 for determination of Strength of rock materials in Triaxial Compression
