Workability, compressive strength and initial surface absorption of laterized concrete

This paper investigated the workability, compressive strength and initial surface absorption of plasticised laterized concrete at the water/cement ratios of 0.30, 0.50 and 0.70. Slump, compressive strength at 7, 14, 21 and 28 days and initial surface absorption after 10 minutes (ISA-10) at 28, 60 and 90 days were determined at the laterite contents of 0, 20, 40, 60, 80 and 100%. ISA-10 was also assessed at 28-day strengths of 20, 25 and 30 N/mm(2). Results showed that superplasticiser dosage increased with increasing content of laterite and for economic dosage laterite content should be limited to 40%. At equal water/cement ratios, compressive strength reduced with increasing content of laterite and ISA-10 increased with increasing content of laterite. The results also showed a strong relationship between ISA-10 and compressive strength and that laterized concrete, when specified on the basis of strength, would have resistance to initial surface absorption comparable with that of the conventional concrete if laterite content is limited to 40%. Hence, for good workability, compressive strength and permeation resistance, laterite content of concrete should be limited to 40%.