Strength and Durability Properties of Cow Dung Stabilised Earth Brick

Abstract

This research, reports on the investigation into the strength and the durability properties of earth brick stabilised with Cow dung. A local earth was stabilised chemically by Cow dung. A better compressive strength at the dry state and after 10 minutes of immersion in water was obtained with cow dung stabilisation at content of 20% by weight of earth. Bricks stabilised with 20% Cow dung contents by weight of earth has a dry and wet compressive strength of 6.64 and 2.27MPa respectively. There is an  increased of about 25%  in the dry compressive strength  of bricks stabilised with 20% cow dung content over that of the plain earth brick without stabiliser  The 20% cow dung content  resulted in lower migration of water into the brick (i e. lower permeability). Also the abrasive resistance increased with increase in the cow dung content up to 20%. The highly decreased in compressive strength after 10 minutes of immersion in water, even with optimum Cow dung content, indicated that appropriate building design that would prevent stabilised earth bricks from coming into direct contact with rainwater is important. The study recommends that appropriate construction specification is necessary to prevent cow dung stabilised earth bricks from coming into any prolonged direct contact with rainwater.

Keywords: cow dung; compressive strength; abrasive resistance; absorption; earth.