Straw Reinforced Unfired and Fired Clay Bricks for Sustainable Building Construction of Meskine Region (Far- North Cameroon)

Abstract

Clay bricks are the most used building materials due to its great mechanical properties and natural abundance. Therefore, this study is performed to further investigate the mechanical properties of straw reinforced unfired (Ufb) and fired bricks (Fb) as building blocks. In this capstone, bricks with the dimensions 40 x 10 x 20 cm were prepared with addition of increasing amounts of straw (0%, 5%, 10% and 15% in wt.). Height samples were compacted; four of them were dried and for other samples were fired at 1050 °C. All the bricks samples were characterized to determine their technological properties. The results for Ufb indicate that bulk density, flexural strength and compressive strength increased up to 10% of straw in the brick formulations and decreased at 15% of addition. At the same time, linear shrinkage, water absorption and porosity decreased slightly with the addition of straw. Hence clay brick containing 10 %wt. % additives showed the best results, the increase starts to have the reversed effect when its percentage is increased beyond this level. For Fb samples results showed that only the porosity increased with straw addition, values of the other parameters decreased with this addition. The addition of straw reinforces the strength of the unfired bricks and enhances the mechanical properties of the composite up to 10% of addition. However addition of straw just increased the porosity of fired brick. Therefore, using clay with addition to straw will represent a good ecological, low energy waste solution to the construction problems as well as recycling constraints. Moreover, no firing use less energy consumption as well and gives more solids bricks for building construction.