Assessment of performance of sandcrete blocks produced by partial replacement of sand with coal bottom ash as fine aggregate

Abstract

Abstract This paper describes the results of an experimental investigation into the assessment of the performance of Sandcrete blocks produced by partially replacing sand with coal bottom ash as fine aggregate. The physical properties of coal bottom ash and sand were carried out in accordance with BS 1377-9 (1990). Sandcrete blocks were produced using hand mould in 0, 10, 20, 30, 40 and 50% replacement levels of sand with the coal bottom ash using cement-sand ratio of 1:6. They were cured at the ages of 7, 14, 21, 28 days and were then subjected to compressive strength tests. Sieve analysis test showed a very similar particle size distribution between sand and coal bottom ash. It was found out that the optimum replacement level was achieved at 20% and the 28-day compressive strength at this level was 3.11N/mm2 which is greater than the minimum strength of 2.8N/mm2 specified by BS 6073-2 (2008). Also, there was a decrease in the weight of the blocks with an increase in coal bottom ash content; this indicates the suitability of using coal bottom ash as a lightweight material in Sandcrete block production.