Effect of cyclic wetting–drying on tensile mechanical behavior and microstructure of clay-bearing sandstone

Abstract The understanding of the weakening mechanism tensile strength rock subjected to cyclic wetting-drying is critical for engineering. Tensile tests were conducted on a total 35 sandstone specimens with different cycles. crack propagation process and acoustic emission characteristics tested samples obtained through high-speed camera system. results indicate that observably reduced after wetting-drying, extent reduction not only related number cycle, but also closely clay mineral content sample. In addition, as cycles increase, effect each single cycle get until it becomes constant. Moreover, initiation penetration time prolonged increases, which indicates weakens stiffness enhances ductility sandstone. Meanwhile, further confirmed ductile behaviour increasing cycle. Furthermore, analysis microstructure composition cycles, concluded main mechanisms sandstones containing minerals are frictional reduction, chemical corrosive deterioration.