Effect of Cassava Starch on the Durability Characteristics of Hollow Sandcrete Block

Abstract

This research investigates the effect of Cassava Starch (CS) floor on the durability characteristics Hollow Sandcrete Block (HSB). Specimens were prepared by adding CS to the cement by weight at percentages of 0.3, 0.7, 1.5, 2.5 and 3.0%. The sandcrete block were cured for 28 days and then tested for compressive strength before subjected to ponding in ironic solutions of sodium hydroxide and sulphuric acid, and sodium chloride.  Five sandcrete block mixes were prepared, each with varying levels of Cassava Starch, to evaluate its effect.

The results showed a reduction in slump value with increasing doses of CS, attributed to the viscous nature of the Cassava Starch paste. Generally, the addition of Cassava Starch to HSB improved resistance to sulphate and chloride attacks, as the muddy-like starch gel blocked the pore spaces in the hardened sandcrete block samples. This reduced the rate at which water and other aggressive chemicals penetrated the blocks. Therefore, the addition of CS to HSB by weight of cement significantly improved the durability characteristic. There is a general increase in the compressive strength of block at varying substitution cement by CS with the maximum increase of 57% was recorded at 2.5% of CS admixture.

The study recommends that HSB made with CS be used for construction in areas prone to sulphate, chlorine, and alkaline attacks.