In recent decades, using byproducts of industries to avoid accumulation and keep environment pure and safe is a necessity. Microsilica is one of such byproducts which are harmful for human health and environment. It contains approximately 95% silicon dioxide which can be used as a material in soil improvement in mixture with lime. Admixing Microsilica Fume and Lime into silty sand causes a reaction between silicon dioxide (SiO_2) of Microsilica and calcium hydroxide (Ca (OH)_2) of Lime and makes calcium silicate crystal which is a hard insoluble material. Such process increases strength parameters of soils. The main objective of this research is evaluation of effects of Microsilica and Lime admixtures on shear strength and swelling of Jandagh-Garmsar railway subgrade. The railway track of iran is located in the central desert of country. Therefore to determine the best composition of Microsilica and Lime to improve mentioned soil, CBR tests have been performed. Results show that the addition of microsilica-lime to the silty sand soil increases the CBR strength and decreases swelling. So microsilica waste material can be successfully used to enhance silty sand soil resistance.
展开▼
