Effects of wetting and drying cycles on the mechanical behaviour of Lightweight Cemented Soils

Abstract

An experimental investigation on the durability of Lightweight Cemented Soils (LWCS) after wetting and drying cycles was developed, focusing on the evolution of their mechanical response. Wetting and drying cycles were performed in climatic chamber to test their mechanical performance as function of number of cycles and the environmental conditions (50% and 90% of Relative Humidity). Unconfined compression tests and triaxial tests were performed on treated specimens after cycles in dry state. Suction of LWCS samples was measured after mechanical tests. Test results show that the wetting-drying cycles and the variations of suction are responsible for the evolution of LWCS mechanical behaviour. Moreover, strength and stiffness of the treated samples are related to the suction level induced by environmental conditions. The degradation of mechanical behaviour is linked to the number of cycles and to the amplitude of suction variation induced, being the latter responsible for mechanical cement bonding destructuration.