Strength and deformation characteristics of cement treated soft Bangladesh clays

Abstract

The strength and deformation characteristics of cement treated soft Bangladesh clays are evaluated through a series of experimental investigations. Based on the rate of strength development, the unconfined compressive strength and cement content relationship can be divided into 3 zones: Inactive Zone, Active Zone and Inert Zone. The stiffness of the cemented clay is a function of cement content and curing time, as the higher cement content and curing time results higher stiffness. The significant increase in apparent preconsolidation pressure and reduction in apparent compression index are observed from consolidation tests for cement treated clay. This implies that the treated clay undergoes structuration (formation of cementation bond) up to their apparent preconsolidation pressure and afterward the destructuration (breaking of cementation bond) takes place. Ductile behavior is associated with lower strength and higher failure strain (high unit deformation). On the contrary, higher strength and lower failure strain (low unit deformation) correspond to brittle behavior. Generally, higher cement content and curing time are the main parameters to cause the stabilised mass become brittle. Effective stress paths correspond to different category of states such as normally consolidated, lightly, moderately and heavily overconsolidated states depend on amount of cementation.