Comparative Study on Compressive Strength of Locally Produced Fired Clay Bricks and Stabilized Clay Bricks with Cement and Lime in Jimma Town.

Abstract

Housing is one of the basic needs of human beings. The local fired brick production technique is the known method of brick making especially in Jimma town. Firing of bricks in local brick production method is conducted by burning of much amount of woods. But this method of firing bricks by burning of woods will affect the environment. Additionally the locale firing technique is difficult to control firing temperature which will result in non-uniform burnt bricks. The major objective of this experimental study was to compare the compressive strengths of locally fired clay bricks and the local unfired cement and lime stabilized clay bricks. And specifically to determine the index properties of soil used for brick production, to determine the compressive strength of locally fired clay bricks and stabilized clay bricks and to compare the determined compressive strength of local fired and stabilized clay bricks with different standards. The index properties of the soil used for local brick production were determined in the laboratory. The contents of the stabilizers were 10%, 12% and 14% lime and cement. The mix ratio was 1:9, 1:7 and 1:6 by volume of stabilizer to clay for 10%, 12% and 14% respectively. Based on the 28 th day mean compressive strength test results, the 10%,12% and 14% cement Stabilized clay bricks have compressive strengths of 2.91Mpa, 3.28Mpa and 3.79Mpa respectively which are better than the mean compressive strength of the locally fired clay bricks which is 2.73Mpa. The 28th day mean compressive strengths of the lime stabilized clay bricks were 2.19Mpa, 2.51Mpa and 2.69Mpa respectively. The Fired Clay Brick fails the minimum mean compressive strength requirement of ES, ASTM and IS standards. But the Stabilized Clay Bricks fulfills the minimum compressive strength requirements of IS standard for stabilized bricks. Finally the cement stabilized clay bricks were better in quality than both locally fired and lime stabilized bricks. Therefore, concerned government bodies, small and micro brick production enterprises and users of local bricks shall adopt the stabilization technique.