Effect of Partial Relacement of Fine Aggregates With Sawdust on the Compressive Strength of Hollow Sandcrete Blocks

The construction industry constantly seeks sustainable and innovative materials to address environmental concerns. This research investigates the viability of utilizing sawdust as a partial replacement for fine aggregates in the production of sandcrete blocks, with a focus on understanding its impact on compressive strength. The primary aim is to explore eco-friendly alternatives without compromising the structural integrity of the blocks. The objectives of this study are two-fold: firstly, to assess the effects of varying percentages of sawdust as a replacement for fine aggregates on the compressive strength of sandcrete blocks; and secondly, to analyze the feasibility of incorporating sawdust into traditional construction practices. The nature of the work involves laboratory experiments, material testing, and statistical analysis to draw conclusive findings.
Methodology employed in this research comprises the systematic replacement of fine aggregates in sandcrete block mixes with varying percentages of sawdust, ranging from 0% to 20%. The investigation revealed that as the proportion of sawdust increased in replacement of sand, water absorption also increased. Notably, the sandcrete hollow blocks made with 80% sand and 20% sawdust replacement after 28 days of curing exhibited the highest water absorption capacity. Furthermore, the density of the hollow blocks decreased as the amount of sawdust used increased, according to the findings of this study.
At 28 days, the compressive strength of sandcrete hollow blocks with 5% sawdust replacement ranged from 1.21 to 1.48 N/mm2, which is below the minimum required standard of 2.0 N/mm2 specified by the Nigeria National Building Code for non-load-bearing walls. Moreover, the compressive strength results for sawdust replacement levels of 10%, 15%, and 20% ranged from 0.71 to 0.55 N/mm2, also falling short of the required minimum standard of 2.0 N/mm2 set by the Nigerian National Building Code for non-load-bearing walls.