Masonry cement – Specification
1988 Edition

IS 3466 mandates the following critical physical properties for masonry cement: maximum 15% residue on a 45-micron sieve (wet sieving), initial setting time not less than 90 minutes and final setting time not exceeding 24 hours as measured by Vicat apparatus, volume stability with Le-Chatelier expansion within 10 mm and autoclave expansion within 1%, compressive strength of mortar cubes (50 mm, 1:3 cement to sand by volume) of at least 2.5 MPa at 7 days and 5 MPa at 28 days, minimum air content of 6% in mortar, and water retention of at least 60% of the original flow after suction. Standard sand conforming to IS 650:1965 is used for testing.

False set in masonry cement is characterized by the ratio of final penetration after 5 minutes of mixing to the initial penetration at 20 seconds, expressed as a percentage. IS 3466 requires this false set ratio to be at least 50%. If false set is detected, the cement must undergo retesting for initial and final setting times after breaking the false set, following IS 4031 (1988) procedures. The setting times after breaking false set must satisfy the standard requirement of initial setting time being no less than 90 minutes and final setting time no more than 24 hours, ensuring the cement’s suitability for masonry applications.

Masonry cement must be packed in bags meeting Indian Standards such as jute sacks (IS 2580), double hessian bituminized, multiwall paper sacks (IS 11761), polyethylene lined jute bags, woven HDPE or polypropylene sacks, among others. Each bag should clearly indicate the manufacturer's name or trademark, the designation 'Masonry Cement', and the net weight or the number of bags per tonne. To distinguish from ordinary Portland cement, bags must carry a brightly colored mark alongside the words 'Masonry Cement'. All bags should be intact and in good condition at the time of inspection to maintain product quality during storage and transport.

IS 3466 recommends testing masonry cement according to IS 4031-1988 methods, including wet sieving on a 45-micron IS sieve to check fineness (maximum 15% residue), setting time determination using the Vicat apparatus (initial setting time ≥ 90 minutes, final ≤ 24 hours), soundness evaluation through Le-Chatelier and autoclave methods (expansion limits of 10 mm and 1%, respectively), compressive strength tests on 50 mm mortar cubes with a 1:3 cement to standard sand mix (minimum 2.5 MPa at 7 days and 5 MPa at 28 days), air content measurement (minimum 6%), and water retention assessment (minimum 60% of original flow after suction). Standard sand for testing must conform to IS 650:1965.

No, masonry cement specified under IS 3466 is not intended for structural concrete, flooring, or foundation applications. The standard explicitly requires that each bag or package be marked with the phrase 'Not for structural concrete, flooring and foundation' to prevent misuse. Masonry cement is formulated primarily for masonry mortar, plastering, and rendering, and for structural or foundation uses, ordinary Portland cement or other structural-grade cements adhering to standards like IS 269 or IS 12269 should be used.