Explanation: The two main groups of coarse aggregates are single-sized aggregates and graded aggregates.

Explanation: Single-size aggregate contains mostly one sieve sized particle. 85-100% of the particular size should be there, with 0-25% of such aggregate retaining on next lower sieve.

Explanation: It consists of aggregates of more than one single grade. It ideally contains particles of size 4.75mm and above in a proportionate amount.

Explanation: Flaky particles have a small thickness compared to the dimensions of other parameters that is width and length.

Explanation: Using the largest size will result in a reduction of cement, water and shrinkage in the concrete mix.

Explanation: Elongation index is obtained as a percentage. E=w1/w2 where w1 is the weight of particles retained in length gauge and w2 is the weight of test sample.

Explanation: As per IS code 383, the sample should contain those aggregates which pass through 12.5mm sieve and are retained on 10mm IS sieve.

Explanation: 2630-2760 kg/cum is a density of granite. 1600 kg/cum is of loose gravel and 1200 kg/cum is that of brick ballast.

Explanation: Classification of coarse grained soils (ISC system) gives the symbol for well graded gravel as GW. For poorly graded, it is GP.

Explanation: All gravel particles have an irregular shape and sharp edge. Sand has a rounded shape. Laminated rocks have flaky shape and crushed rocks have an angular shape.