SMALL STRAIN BEHAVIOUR OF CEMENT TREATED SINGAPORE MARINE CLAY

Abstract

By conducting a series of bender element test, resonant column test, local strain test and unconfined compressive test, this study mainly advances the understanding of key parameters influencing small-strain shear modulus of cement-treated clay. The results show that: (i) Unconfined compressive strength qu and maximum shear modulus Gmax and can be quantified by mix ratios and curing periods. qu is the dominant factor controlling the location of the normalized shear modulus G/Gmax degradation curve. (ii) An increase in mean effective stress p’ could lead to the increase of shear modulus, especially when p’ is greater than the primary yield stress. (iii) The stress history also plays a great role in the development of Gmax, especially when the experienced maximum stress p’max exceeds p’py. For one certain p’, the specimen experienced higher maximum stress p’max is found to have a greater growth in shear stiffness. In addition to the over-consolidation ratio, the initial stress state could also affect the growth of Gmax greatly. (iv) Both of effective confining pressure (p’>p’py) and stress history with p’max>p’py could significantly increase the ductility of cement-treated clay.