Coarse Aggregate. Coarse aggregate shall consist of crushed or broken stone and be hard, strong, dense, durable, clean and of proper gradation and free from skin and coating likely to prevent proper adhesion of mortar. The aggregate shall generally be cubical in shape and as far as possible flaky, elongated pieces shall be avoided. It shall generally comply with the provisions of I.S. 383‑1970 and I.S. 515‑1959. Stone shall have no deleterious reaction with cement. The coarse aggregate shall be of the following sizes: Normal cement concrete of 100mm and above thickness ‑ graded 20mm and below Cement concrete topping thickness 40mm and above ‑ graded from 12mm and below Mass cement concrete of 500mm and above ‑ graded 38mm and below Grading tests shall be taken in the beginning and at change of source or material. Where required, by the Engineer, tests indicated in I.S. 383‑ 1970 and I.S. 456‑1978 shall be carried out in an approved laboratory at the Contractor's cost to show the acceptability of the material. Coarse aggregate of a porous nature where absorption of water after 24 hours immersion in water, is more than 5 percent by weight, shall not be used.
Appears in 3 contracts
Sources: Contract Agreement, Procurement Agreement, Contract Agreement