SMALL-STRAIN SHEAR MODULUS of CEMENT- ADMIXED CLAY
An experimental study is conducted to measure small-strain shear modulus of clay-cement mixture using bender element apparatus having been setup in a triaxial cell. In order to reduce the risk of variation in plastic behavior of natural clays, pure kaolinite was selected as the cohesive material. The bender element test was chosen because it provides reliable and repeatable small strain shear modulus measurements and allows for conducting the test under vibration with different frequencies. Bender element tests were conducted on cement treated soils and the results were then analyzed to study the variations in stiffness properties of soil specimens at different cement contents, confining pressures, and compaction moisture contents. Treated specimens were kept under room temperature in a 100% humidity –controlled room for seven days curing period. Based on the obtained results increasing the cement ratio has a significant effect on the small-strain shear modulus of the treated soils, and this effect enhances with increasing the moisture content. Rates of stiffness enhancements due to cement content and compaction moisture content are quantified and presented.