Experimental study of triaxial strength and deformation of single jointed sandstone under cyclic loading

To study the deformation evolution rule and strength characteristics of jointed sandstone specimens under cyclic loading, the monotonic loading and cyclic loading tests through single jointed sandstone under different confining pressure were conducted. The results show that with the increase of confining pressure, the peak strength of jointed sandstone specimens increases with monotonic loading and cyclic loading. Under triaxial cyclic loading, the evolution of elastic modulus of jointed sandstone experiences three stages: increasing obviously, decreasing sharply and stabilizing after peak. The jointed sandstone specimens are subjected to shear failure in triaxial monotonic and cyclic loading. Under lower confining pressure(5,15 MPa), the damage caused by cyclic loading is more severe than that caused by monotonic loading. Under higher confining pressure(25,35 MPa), the failure modes of monotonic and cyclic loading are similar. © 2020, Editorial Board of Journal of CUMT. All right reserved.