|
|
|
| Study on the evolution characteristics of rock deformation and post-peak energy under different loading methods |
| YANG Xiaobin1，CHENG Hongming1，2，PEI Yanyu1 |
| (1. School of Emergency Management and Safety Engineering，China University of Mining and Technology，Beijing 100083，China；2. School of Coal Engineering，Shanxi Datong University，Datong，Shanxi 037003，China)
|
|
|
|
|
Abstract In order to study on the evolution characteristics of rock deformation and post-peak energy under different loading methods，the triaxial tests with pre-peak unidirectional loading and post-peak cyclic loading，and the triaxial tests with pre-peak and post-peak cyclic loading were carried out with different confining stress. Results showed that at the same pre-peak stress level，the deformation caused by cyclic loading was little smaller than unidirectional loading，meanwhile，the specimens of cyclic loading appeared non-penetrating tiny crack with different lengths and angles，which developed form the end to the main crack，and the angles of main crack were relatively large under the same confining stress. The post-peak stress drop form of two loading methods was similar，while the total energy(W)，the dissipation energy(Wd)，and the frictional dissipation energy(Wf) of specimens during the process of stress drop caused by cyclic loading were smaller than unidirectional loading，and the elastic strain energy were larger. The residual strength stage of two loading methods showed ideal plastic deformation characteristics，and the residual strength was decreased with the increasing number of cycles. The W，the Wd，and the Wf，and the We，and the frictional dissipation energy per unit strain(wf) of rock specimens at residual strength stage of cyclic loading test were larger than unidirectional loading test，and the wf of two loading methods had confining pressure effect.
|
|
|
|
|
|
|
|
|
2020, Vol. 39 
