Effect of varying sand content in laterized concrete

Abstract

Tests are reported on concrete containing crushed granite, sharp sand and fine laterite in varying proportions. The percentage of sand by weight of the total fine aggregate was varied in steps of 25% up to a maximum of 100% corresponding to normal concrete. The standard mixes which were investigated were 1:2:4, 1:1 1 2 :3, and 1:1:2 . The compressive strengths were determined up to 84 days. The most suitable mix for structural applications was found to ben 1:1 1 2 :3 without about 0.65 water/cement ratio provided that the percentage laterite content is kept below 50%. Compressive strength of not less than 25 N/mm 2 was obtainable at 28 days for this mix with laterite content of about 25–50%. The density of laterized concrete and its compressive strengths show that laterized concrete is a dense and structurally sound material. The modulus of elasticity of the recommended mix of laterized concrete ( 1:1 1 2 :3 ) may be as high as 18–20 kN/mm 2 if the mix is well controlled.