STRUCTURAL PERFORMANCE OF SILICATE -LIMESTONE COMPRESSED BRICKS

Abstract

Present concerns for sustainable development have led to a revival of traditional building practices using natural or recycled resources. Silicate-limestone bricks are alternative building materials, which are significantly cheaper than using conventional concrete block sand are environmentally sustainable. The use of limestone, which makes up about 10% of the total volume of all sedimentary rocks saves environmental pollution, energy and manufacturing cost. In order to demonstrate silicate limestone as a suitable appropriate construction material, tests on blocks and walls made from limestone and silicate materials were investigated to establish their structural performance and suitability for eco-friendly house construction on the Africa continent. Water absorption and the density tests of the bricks were done, and the physical properties of silicate limestone compressed bricks were observed and analyzed as the lime content was varied between 0 to 100%. The results obtained show that as lime content increases, water absorption also increases. Nevertheless, the results were within the recommended values i.e. less than 15%.ofmass ratio. The density of bricks decreased when lime contents were added. They were all considered as heavy blocks because the values were more than 1000kg/m3. From these two tests, it was noted that above 60% of lime content, the bricks become unstable. The compressive and flexural tests on the bricks were done using a Universal Testing Machine for vertical and transversal loading for the determination of the crushing strength. These tests were done compared to the blocks available on the Kenya market. Compared to the blocks available in the Kenya market, the silicate limestone had better strength, with the exception of bricks at 100% of lime content, in which the compressive strength of 1.324 MPa was lower than the minimum requirement for compressive strength, which is 2.5 MPa. The tests done on the bricks showed clearly that the optimum percentage of lime replacement in terms of physical and strength properties was 60%.The silicate limestone bricks wall was made with this percentage of lime content and compared to clay brick and natural stone blocks wall. The results of these tests showed that the strength properties of natural stone wall were higher than those of silicate limestone wall, which is contrary to the results from the compressive strength of their unit blocks.