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.
Material Testing for Quality Control
For Buildings/Bridges
Properties of Construction Material change from place to place. Sometimes they may affect the strength and durability of the Structure, based on their Engineering Properties like Grain size, Specific Gravity, Flakiness, Elongation, etc. of Aggregates. However, the Compressive Strength of Cement also gets reduced on its defective storage for large durations in godowns before it being used at the Site. Hence, it is required to confirm the physical properties of Cement well in advance before its usage in Construction Work. Another reason by virtue of which the Compressive Strength and Durability of Concrete quite often gets reduced is due to excess/less quantity of Water Cement ratio being used in its preparation. Whereas, the presence of soluble salts in Water used in Construction Work may also damage the Building after certain lapse of Construction Time. Therefore, it is necessary to check/test the materials being used in construction for their inherent properties before starting the Construction Work as per various relevant IS standards.
Hence, the need arise for proper Quality Control Tests like Cement Concrete Mix Design, etc. being done for various Civil Engineering Structures for their Safe Design.
Hence, the need arise for proper Quality Control Tests like Cement Concrete Mix Design, etc. being done for various Civil Engineering Structures for their Safe Design.
For Roads
The materials available for road construction are found to possess varying properties from location to location and their source (quarry), which in turn decides on the quality of road constructed. In order to assure and guarantee the quality of road work, the testing needs arise. Therefore, properties of all individual constituents used in Road Construction may generally be tested for their engineering properties so as to ensure proper stable roads having larger duration of their life time conforming to their stability requirements, density etc. as per codal provisions (mainly MOSRT & H specifications). Hence, the need arises for proper quality control checks like Bituminous Mix Design being done for all type of roads which shall include Design for Bituminous Macadam (BM), Dense Bituminous Macadam (DBM), Mix Seal Surfacing (MSS), Semi Dense Bituminous Concrete (SDBC) and Bituminous Concrete (BC), etc.
Aggregate
Sieve Analysis as per IS:2386 (Part I) - 1963
This is the method of determination of particle size distribution of fine, coarse and all-in-aggregates by sieving or screening.
Flakiness Index as per IS:2386 (Part I) - 1963
This is the percentage by weight of particles in the aggregate whose least dimension (thickness) is less than three-fifths of their mean dimension. The test is not applicable to sizes smaller than 6.3 mm.
Elongation Index as per IS: 2386 (Part I) - 1963
This index of an aggregate is the percentage by weight of particles whose greatest dimension (length) is greater than one and four-fifths times their mean dimension. This test is not applicable to sizes smaller than 6.3 mm.
Aggregate Crushing Value as per IS:2386 (Part IV) - 1963
The ratio of the weight of fines (passing 2.36 mm IS Sieve) formed, under 40 tonnes compressive load applied gradually to the total sample weight expressed as a percentage is known as crushing value.
Determination of Ten Percent Fines Value as per IS:2386 (Part IV) - 1963
The apparatus, with the test sample and plunger in position, shall be placed in the compression testing machine. The load shall be applied at a uniform rate so as to cause a total penetration of the plunger in 10 minutes of about:
15.00 mm for rounded or partially rounded aggregates (for example, uncrushed gravels),
20.00 mm for normal crushed aggregates, and
24.0 mm for honeycombed aggregates (for example, expanded shales and slags).
These figures may vary according to the extent of the rounding or honeycombing.
After reaching the required maximum penetration, the load shall be released and the whole of the material removed from the cylinder and sieved on a 2.36 mm IS Sieve. The fines passing the sieve shall be weighed, and this weight expressed as a percentage of the weight of the test sample. Normally this percentage will fall within the range 7.5 to 12.5, but if it does not, a further test shall be made at a load adjusted as seems appropriate to bring the percentage fines within the range of 7.5 to 12.5.
(*Note: - The formula given in 3.5 may be used for calculating the load required.)
A repeat test shall be made at the load that gives a percentage fines within the range 7.5 to 12.5.
The load required to produce 10 percent fines shall be reported to the nearest whole number for loads of 10 tonnes or more, the nearest 0.50 tonne for loads of less than 10 tonnes.
After reaching the required maximum penetration, the load shall be released and the whole of the material removed from the cylinder and sieved on a 2.36 mm IS Sieve. The fines passing the sieve shall be weighed, and this weight expressed as a percentage of the weight of the test sample. Normally this percentage will fall within the range 7.5 to 12.5, but if it does not, a further test shall be made at a load adjusted as seems appropriate to bring the percentage fines within the range of 7.5 to 12.5.
(*Note: - The formula given in 3.5 may be used for calculating the load required.)
A repeat test shall be made at the load that gives a percentage fines within the range 7.5 to 12.5.
The load required to produce 10 percent fines shall be reported to the nearest whole number for loads of 10 tonnes or more, the nearest 0.50 tonne for loads of less than 10 tonnes.
Aggregate Impact Value as per IS:2386 (Part IV) - 1963
The ratio of the weight of fines (passing 2.36 mm IS Sieve) formed, under 15 times impact of a metal top or hammer weighing 13.50 to 14.00 Kg fall freely between the vertical guides from a height of 380 mm - 5 mm to the total sample weight expressed as percentage is known as impact value test shall be made on aggregate passing 12.50 mm and retained on 10.00 mm Sieve,
Aggregate Abrasion Value by Los Angeles Machine as per IS:2386 (Part IV) - 1963
The test sample and the abrasive charge shall be placed in the Los Angeles Machine and rotated at a speed of 20 to 33 rev/min. For gradings A, B, C and D the machine shall be rotated for 500 revolutions; for grading E, F and G, it shall be rotated for 1000 revolutions. At the completion of the test, the finer portion shall be sieved on a 1.70 mm IS Sieve. The difference between the original weight and the final weight of the test sample shall be expressed as a percentage of the original weight of the test sample and is known as abrasion valuemade on aggregate passing 12.5 mm, IS Sieve and retained on a 10 mm IS Sieve. If the standard size is not available, other size up to 25 mm may be tested as per table given below:-
A = Weight of total Sample.
[A] Aggregate to be used in concrete for wearing surfaces - 30%
[B] Aggregate to be used in other concrete - 50%
A = Weight of total Sample.
[A] Aggregate to be used in concrete for wearing surfaces - 30%
[B] Aggregate to be used in other concrete - 50%
Coarse Aggregate
Coarse aggregate shall consist of clean, hard, strong, dense non porous and durable pieces of crushed stone, crushed gravel, natural gravel or a suitable combination thereof other approved inert material. It shall not contain pieces of disintegrated stones, soft, flaky elongated particles, salt alkali, vegetable matter or other deleterious materials in such quantities as to reduce the strength or durability of the concrete, or to attack the embedded steel. It shall comply with IS: 383.
The nominal maximum size of aggregates shall usually be restricted to 10 mm. Less than the minimum clear distance between individual cables or individual untensioned steel reinforcement or 10 mm. Less than the minimum cover to untensioned steel reinforcement, whichever is smaller. A nominal size of 20 mm. coarse aggregates shall generally be considered satisfactory for prestressed concrete work.
The nominal maximum size of aggregates shall usually be restricted to 10 mm. Less than the minimum clear distance between individual cables or individual untensioned steel reinforcement or 10 mm. Less than the minimum cover to untensioned steel reinforcement, whichever is smaller. A nominal size of 20 mm. coarse aggregates shall generally be considered satisfactory for prestressed concrete work.
Fine Aggregate
Fine aggregates shall consist of hard, strong, durable, clean particles of natural sand, crushed stone or crushed gravel or suitable combination of natural sand and crushed stone or gravel. They shall not contain dust, lumps, soft or flaky materials, mica and other deleterious materials in such quantities as would reduce the strength or durability of concrete or attack the embedded steel. Fine aggregates shall conform to IS: 383 - 1970.
Water
Water used for mixing and curing shall be clean and free from injurious amounts of oils, acids, alkalis, salts, sugar, organic materials or other substances that may be deleterious to concrete or steel. Potable water is generally considered satisfactory for mixing concrete. As a guide the following concentrations represent the maximum permissible values :
- To neutralize 100 ml sample of water using phenolphthalein as an indicator, it should not require more than 5 ml of 0.02 normal NaOH.
- To neutralize 100 ml sample of water using methyl orange as an indicator, it should not require more than 25 ml of 0.02 normal H2SO4.
- To neutralize 100 ml sample of water using phenolphthalein as an indicator, it should not require more than 5 ml of 0.02 normal NaOH.
- To neutralize 100 ml sample of water using methyl orange as an indicator, it should not require more than 25 ml of 0.02 normal H2SO4.
Cement
(1) Ordinary Portland Cement conforming to IS: 269 - 1989
(2) Portland slag cement conforming to IS: 435 - 1989 but with not more than 50 percent slag content
(3) Rapid hardening Portland cement conforming to IS: 8041
(4) High strength Portland cement conforming to IS: 8112 - 1989
(2) Portland slag cement conforming to IS: 435 - 1989 but with not more than 50 percent slag content
(3) Rapid hardening Portland cement conforming to IS: 8041
(4) High strength Portland cement conforming to IS: 8112 - 1989
Admixture
Admixture may be provided in conformity with IS: 1343.
Cement Concrete Mix design (This is done as per IS: 10262 - 1982 revised in 2009)
The determination of the proportion of cement, aggregates and water to attain required strengths shall be made by designing the concrete mix. The concrete mix shall be designed as per IS: 10262 (Recommended Guidelines for Concrete Mix Design) to have a target mean strength defined as fck + 1.65.
Maximum quantity of cement shall not be more than 540 Kg/cum of concrete.
Maximum quantity of cement shall not be more than 540 Kg/cum of concrete.
Calculation of Aggregate Content
With the quantities of water and cement per unit volume of concrete and the ratio of fine to total aggregate already determined, the total aggregate content per unit volume of concrete may be calculated from the following equations:
V = [ W + C / Sc + 1/ p x fa / Sfa] x 1/100, and
V = [ W + C / Sc + 1 / 1- p x Ca / Sca ] x 1 / 1000
where,
V = absolute volume of fresh concrete, which is equal to gross volume (m3) minus the volume of entrapped air,
W = mass of water (kg) per m3 of concrete,
C = mass of cement (kg) per m3 of concrete,
Sg = specific gravity of cement,
P = ratio of fine aggregate to total aggregate by absolute volume, fa, ca = total masses of fine aggregate and coarse aggregate (kg) per m3 of concrete respectively and
Sfa, Sca = specific gravities of saturated surface dry fine aggregate and coarse aggregate respectively.
IS 516: 1959 Test for strength of concrete can also be referred in this case.
V = [ W + C / Sc + 1/ p x fa / Sfa] x 1/100, and
V = [ W + C / Sc + 1 / 1- p x Ca / Sca ] x 1 / 1000
where,
V = absolute volume of fresh concrete, which is equal to gross volume (m3) minus the volume of entrapped air,
W = mass of water (kg) per m3 of concrete,
C = mass of cement (kg) per m3 of concrete,
Sg = specific gravity of cement,
P = ratio of fine aggregate to total aggregate by absolute volume, fa, ca = total masses of fine aggregate and coarse aggregate (kg) per m3 of concrete respectively and
Sfa, Sca = specific gravities of saturated surface dry fine aggregate and coarse aggregate respectively.
IS 516: 1959 Test for strength of concrete can also be referred in this case.
Tests for Bitumen
Penetration Test as per IS: 1203 - 1978
Penetration of bitumen material is the distance in tenth of millimeter. That a standard needle will penetrate vertically into sample of the material under standard condition, temperature, load and time. This test determines hardness or consistency of bitumen. This test is conducted for identification of grade of bitumen.
Softening Point Test as per IS: 1205 - 1978
The Softening point is the temperature at which the substance attains particular degree of softening under specified condition of test. It is usually determined by Ring and Ball test.
Viscosity Test as per IS: 1206 (Part I) - 1978 Industrial Viscosity
The property of a fluid by which it resists flow due to internal friction, is by determining the time taken by 50 cc of the material to flow from a cup through a specified orifice under standard conditions of test and at specified temperature.
Ductility Test as per IS: 1208 - 1978
The ductility of a bituminous material is measured by the distance in centimetres to which it will elongate before breaking when a briquette specimen of the material of the form prescribed are pulled apart at a specified speed and at a specified temperature.
Flash Point and Fire Point as per IS: 1209 - 1978
The flash point of a material is the lowest temperature at which the application of test flame causes the vapours from the material momentarily catch fire in the form of a flash under specified conditions of test.
The fire point is the lowest temperature at which the application of test flame causes the material to ignite and burn at least for 5 s under specified conditions of test.
The fire point is the lowest temperature at which the application of test flame causes the material to ignite and burn at least for 5 s under specified conditions of test.
Bitumen Mix Design (MOSRT & H)
Paver Block as per IS: 15658:2006
Method for the determination of Compressive Strength.
Dimensions and plan areas of the specimens shall be measured as per reference IS code. The blocks shall be stored for at least 24 Hours 244 h in water maintained at a temperature of 20°c ± 5°c. The bearing plates of the testing machine shall be wiped clean. The specimens
are aligned with those of the bearing plates.
Calculation :-
The apparent compressive strength of individual specimen shall be calculated by dividing the maximum load (in/V) by the plan area (in mm). The corrected compressive strength shall be calculated by multiplying the apparent compressive strength by the appropriate correction factor from Table. The strength shall be expressed to the nearest 0.10 N/mm. Correction Factors for Thickness and Arris / Chamfer of Paver Block for calculation of Compressive Strength.
Calculation :-
The apparent compressive strength of individual specimen shall be calculated by dividing the maximum load (in/V) by the plan area (in mm). The corrected compressive strength shall be calculated by multiplying the apparent compressive strength by the appropriate correction factor from Table. The strength shall be expressed to the nearest 0.10 N/mm. Correction Factors for Thickness and Arris / Chamfer of Paver Block for calculation of Compressive Strength.
For other thickness of paver blocks between 50 mm and 120 mm, linear extrapolation of correction factor shall be made.
Abrasion Resistance
Square shaped specimens measuring 71.0 ± 0.5 mm shall be cut from the block (specimen selected) and testing surface of the specimen shall be centrally loaded with 294 ± 3N on grinding disc. Disc shall be stopped after one cycle of 22 revolutions at a speed of 30 rpm. the specimen turned 90 in clockwise direction and repeat the test 16 times.
The abrasive wear of the specimen calculated as mean loss in specimen volume V from the equation.
ΔV = Δm/PR when
ΔV = loss in volume in mm3
Δ m = Δloss in mass in gms
ΔPR = density of the specimen in g/mm3
ΔV = Δm/PR when
ΔV = loss in volume in mm3
Δ m = Δloss in mass in gms
ΔPR = density of the specimen in g/mm3
Flexural Strength / Breaking Load
The Flexural strength of the specimen shall be calculated as:-
Fb = 3Pl / 2bd2
Fb = Flexural Strength, in N/mm2
P = Maximum Load, in N
l = Distance between central lines of the supporting rollers, in mm
b = Average width of block, in mm
d = Average thickness, in mm
The maximum load P shall be reported as the breaking load, nearest to 1 N.
Fb = 3Pl / 2bd2
Fb = Flexural Strength, in N/mm2
P = Maximum Load, in N
l = Distance between central lines of the supporting rollers, in mm
b = Average width of block, in mm
d = Average thickness, in mm
The maximum load P shall be reported as the breaking load, nearest to 1 N.
