Effect of wetting - drying cycles on physical, mechanical and failure properties of sandstone

In many environments, rocks are usually exposed to continuous wetting and drying. The number wetting-drying cycles will exacerbate weathering and reduce the mechanical properties of the rock and due to that process, geological disasters occur. The effects of alternating wetting and drying cycles on rocks degradation have a greater impact than long-time soaking, which is a critical issue in the sustainability of rock mass engineering. In this research , sandstone specimens of Lalun Formation in Loshan area were used and the effect of wetting-drying cycles (0, 1, 4, 16 ) on physical properties including effective porosity, P-wave velocity, dry and saturated specific weight and mechanical properties including indirect tensile strength, uniaxial compressive strength, elasticity modulus, triaxial compressive strength, cohesion and internal friction angle was investigated. The results indicate that by increasing the wetting-drying cycles, Effective porosity increased but dry and saturated specific weight, P-wave velocity, tensile strength, uniaxial compressive strength, triaxial compressive strength, elasticity modulus, cohesion and internal friction angle decreased.