Author(s): HE Ming-ming, CHEN Yun-sheng, LI Ning, ZHU Cai-hui, Institute of Rock and Soil Mechanics, Xi’an University of Technology
Pages: 1805-1812
Year: 2015 Issue:  8
Journal: Journal of China Coal Society
Keyword:  sandstone; cyclic loading; cyclic softening and hardening; dissipated energy evolution; deformation;
Abstract: In order to investigate the deformation,cyclic softening and hardening and energy properties of sandstone,the tests of sandstone samples under different amplitudes cyclic loading were conducted on WDT-1500 reactive material testing machine. A dissipated energy evolution equation with cycle number was founded. In the tests,the following conclusion could be drawn. The lateral and axial deformation characteristics of sandstone are different at the initial and constant speed stages,when the upper cyclic loading is above or below yield stress. The yield stress of sandstone under uniaxial compression could be the peak stress corresponding to the point transferring from cyclic softening to cyclic hardening. The characteristics of dissipated energy are different in the whole process,and the shape of evolution can be U shape or L shape. A dissipated energy evolution equation is proposed for sandstone,and the predicted energy dissipation behavior is consistent with the observations in the tests,which shows that the evolution equation is capable of describing the energy dissipation behavior of sandstone.