Effect of Sawdust on the Compressive Strength of Concrete

Abstract

This study was undertaken to investigate the properties of concrete produced by partial replacement by weight of sand with sawdust generated from different species of wood. The sawdust used in this investigation consist of the wood species, Piptadeniastrum africanum (leguminosae family), Triplochiton scleroxylon (sterculiaceae family) and Celtis mildbraedii, locally known as Dahoma, Wawa and Essa respectively. The addition of sawdust to the concrete was done by 5% increment up to 25% by weight of the fine aggregate. Concrete cubes of size 150mm x150mm x 150mm were prepared after batching and mechanical mixing for the compressive strength tests.  The compressive strength tests were carried out after 28 day curing of the concrete cubes in accordance with BS EN12390-3:2009 series. Sawdust blend concrete from wawa - a lightwood species gave the best result of 5.3 N/mm² at 28 days. The optimum replacement of sand with sawdust has been found to be 5% for lightwood species.

Keywords: Batching, Mechanical mixing, Sawdust, Compressive strength.