Improvised Techniques of Earth Bricks Stabilisation with Cassava Starch

Abstract

Compressed Earth Bricks technology is anchored in an initial concern to provide a new, economically and socially relevant response to housing production for the World's very poor. As at now the information fully available on stabilisation of Compressed Stabilised Earth Bricks (CSEBs) with alternative materials are on partial replacement of cement but not the use of cassava starch alone. This work is aimed at improvising Earth Brick Stabilisation techniques with cassava starch as the only binder. The adopted techniques are 'Instant Dry Mix (IDM)'; 'Delayed Dry Mix (DDM)'; and 'Cooked Paste Mix (CPM)'. Mechanical properties of the specimens were determined after curing for 7, 14 and 28 days. From the results of Compaction Characteristics and Compressive Strength of samples at 28 days, the CPM technique performs best with compressive strength of 2.71N/mm2, greater than the NBRRI minimum requirement of 1.65 N/mm2 for compressed earth bricks. The volume of cassava starch increases when cooked, therefore, it is concluded that CPM process is the most appropriate technique of cassava starch bricks (CSBs) stabilisation that can be cost effective in low-cost housing development. Bricks produced using CPM can be applied for the construction of walls in low rise buildings with proper protection from dampness as CS is susceptible to water.