Effect of Sugarcane Bagasse Ash on the Engineering Properties of Blended Sandcrete Blocks

Abstract

This research investigates the effect of Sugarcane Bagasse Ash (SBA) on the engineering properties of sandcrete blocks produced with optimal amount of blended lateritic and marine sand. Sandcrete hollow blocks (450mm x 225mm x 225mm) were made by blending varying contents of marine sand and lateritic sand using the nominal mix ratio of 1:6 (cement: sand). Marine and clean lateritic sand were blended at intervals of 10%. A total of 90 sandcrete blocks were casted and the compressive strengths of the blocks determined at 7, 14 and 28 days. The 28 day compressive strength of mixes containing 0, 10, 20, 30, 40, 50, 60, 80 and 100% marine sand were, 4 .47, 5.10, 5.25, 5.33, 5.20, 4.63, 4.58, 3.88 and 3.76 N/mm2 respectively. The 28 days strength for both blends of sand exceeded the minimum strength value of 3.45N/mm2 specified by BS 6073:2.Sandcrete blocks made with 30:70 marine-lateritic sand blending ratio produced the highest compressive strength. Using this ratio, 90 sandcrete blocks were casted by replacing cement with Sugar Bagasse Ash in the ratio of 0%, 5%, 10% 15% 20% and 25% by weight. The blocks were tested for compressive strength, density, water absorption and durability. The 28 day compressive strength were 5.33, 5.29, 5.18, 4.71, 3.42, 3.08 N/mm2 for 0, 5, 10, 15, 20 and 25 % replacement respectively. Upto 15% replacement levels met the minimum compressive strength recommended in standards. The results for water absorption, density and durability of the blocks were within the acceptable limits.