Material Testing Service
Price On RequestACCORDING TO IS: 2386-1963 SIEVE ANALYSIS (Part 1)
Sieve analysis helps to determine the particle size distribution of the coarse and fine aggregates. This is done by sieving the aggregates . In this we use different sieves as standardized by the IS code and then pass aggregates through them and thus collect different sized particles left over different sieves.
FLAKINESS ELONGATION INDEX (Part 1)
This test is used to determine the particle shape of the aggregate and each particle shape being preferred under specific conditions.The significance of flakiness elongation index is as follows;The degree of packing of the particles of one size depends upon their shape.Due to high surface area to volume ratio, the flaky and elongated particles lower the workability of concrete mixes.
DELETERIOUS MATERIALS (Part 2)
Aggregates Quality should consist of naturally occurring (crushed or uncrushed) stones, gravel and sand or combination thereof. They should be hard, strong, dense, durable, clear and free from veins and adherent coating, and free from injurious amounts of disintegrated pieces, alkali, vegetable matter and other deleterious substances. As for as possible, flaky, scoriaceous and elongated pieces, pieces are avoided. Visual inspection of gravel and natural sand is necessary for presence of clay lumps, clay coating, silt, grading and shape, while for crushed aggregates and sand inspection is necessary for stone dust, flaky shape and grading. If clay dust silt or mud is present and not removed/reduce through washing, it may produce lower strength concrete. The presence of mica should be investigate in fine aggregate and should also make suitable allowances for the possible reduction in the strength of concrete or mortar. The aggregate should not contain harmful organic impurities, excess to the limit specified.
SPECIFIC GRAVITY AND WATER ABSORPTION (Part 3)
Specific gravity, a low specified gravity indicates to high porosity, which results in poor durability and low strength. The concrete density is greatly depending on the specific gravity. A porous should not be permitted, unless specified.
BULK DENSITY VOIDS (Part 3)
Bulk density of aggregates is the mass of aggregates required to fill the container of a unit volume after aggregates are batched based on volume. It depends on the packing of aggregate i.e. Either loosely packed aggregates or well dense compacted aggregates. In case, if the specific gravity of material is known, then it depends on the shape and size of particles. It is because, if all the particles are of same size than packing can be done up to a very limited extent. If the addition of smaller particles is possible within the voids of larger particles than these smaller particlesenhance the bulk density of the packed material. Shape of the particles also influence very widely, because closeness particles depends on the shape of aggregates.
BULKING OF FINE AGGREGATE (Part 3)
The volume increase of fine aggregate due to presence of moisture content is known as bulking. Fine sand bulks more as compared to coarse sand. Extremely fine sand particularly the manufactured fine aggregate bulks as much as about 40%. The moisture present in aggregate forms a film around each particle. These films of moisture exert a force, known as surface tension, on each particle. Due to this surface tension each particles gets away from each other. Because of this no direct contact is possible among individual particles and this causes bulking of the volume.