Effect of Bentonite, Fly Ash and Silica Fume cement injections on uniaxial compressive strength of granular bases

Injection is one of the methods to improve the engineering properties of bases. Various additions as well as cement are used for preparations of injection blends in order to lower costs and reach better results. For this purpose in the preparation of the injection blends, Bentonite (B), Fly Ash (FA) and Silica Fume (SF) were used at the ratios of 0-0.5-1-3%, 10-20-30-40% and 0-5-10-20%, respectively. Taguchi method was applied for the experiment and L16 Orthogonal (OA) with three factors and four levels were chosen. Granular bases having 0.70 relative density was settled into a cylindrical mold to which injection blends were injected. Effect of B, FA and SF over the uniaxial compressive strength of the samples of 7, 14, 28 days that have been prepared in this manner was investigated. In results of the experiments it was observed that the most effective parameter over the uniaxial compressive strength of 7, 14 and 28 days was silica fume. © 2014 Korean Society of Civil Engineers and Springer-Verlag Berlin Heidelberg.