ASSESSMENT OF SAWDUST AS PARTIAL REPLACEMENT FOR FINE AGGREGATE IN CONCRETE SLAB

Abstract

The cost of construction activities is a major concern in developing countries, because of rise in construction materials. This was the reason for assessingpartial replacement of sand with sawdust as fine aggregate in concrete slab. Concrete slabs with dimension 800 × 300 × 75mm at varying percentage composition of sand with sawdust from 0 to 10% at 2.5% interval in the concrete were produced. The flexural strength test was carried out on each replacement at 7, 14, 21 and 28^th dayrespectively. Ultimate strength was developed at the point of failure. The flexural strength developed at 28^th day for 0, 2.5, 5.0, 7.5 and 10% were 6.8, 6.0, 5.4, 5.1 and 4.5 N/mm²respectively. The optimal replacement recommended was 2.5% and the least was 10%. The results indicated that concrete containing sawdust as partial replacement for sand can be used for concrete slab, thereby reducing cost of construction works.