Assessing the influence of aggregates and cement type on the properties of roller compacted concrete

Abstract

Roller compacted concrete pavement is suitable for heavy traffic and harsh environment. In the present investigation, roller compacted concrete slab samples have been prepared using two types of aggregates, (crushed and rounded), and two types of cement binder, (ordinary Portland and sulphate resistant). Cubes and beam specimens have been extracted from the slab samples with the aid of diamond saw. Specimens were tested for bulk density, ultrasound pulse velocity, compressive and flexural strength. It was observed that crushed aggregates exhibit higher compressive and flexural strength, and higher density regardless of the cement content or type of cement as compared with rounded aggregates. The compressive strength of mixtures with crushed aggregates is higher than that of mixtures with rounded aggregates by (9.4, 37.2, and 47.1) % and (5.7, 26.1, and 31.2) % for mixtures with (10, 12, and 16) % of Portland and sulphate resistance cement respectively. The flexural strength for mixtures with crushed aggregates is higher than that of mixtures with rounded aggregates by (19.7, 18.4, and 15) % and (13.4, 14.3, and 16.5) % for mixtures with ordinary and sulphate resistance cement content of (10, 12, and 16) % respectively. The bulk density for mixtures with crushed aggregates is higher than that of mixtures with rounded aggregates by (0.2, 0.65, and 2.5) % and (0.4, 1.0, and 2.3) % for mixtures with ordinary and sulphate resistance cement content of (10, 12, and 16) % respectively. Crushed aggregates are recommended for the roller compacted concrete to enhance the required flexural strength.