1. College of Emergency Management and Safety Engineering,China University of Mining & Technology ( Beijing),Beijing　 100083,China; 2. College of Architecture and Civil Engineering,North China University of Technology,Beijing　 100144,China

In the practice of geotechnical engineering,the frictional sliding of rock interface can cause engineering in- stability,which seriously threatens people’s life and property safety. The slippage problem of rock interface is often in a reciprocating state. At present,most scholars are interested in rock interface slippage. The problem is often built in a single loading state,but less research is on reciprocating loading states. In order to study the evolution characteristics of interface slip field under cyclic loading,a double shear model test study of granite specimen under constant confining pressure was designed and carried out. The CCD camera was used to collect the speckle image during the interface slip process,and the evolution characteristics of the displacement field and frictional slip displacement of the granite speci- men during the experimental loading were carried out by using the white light numerical speckle correlation method for research and analysis. The results show that ① under the action of cyclic loading,with the increase of the number of cycles,the displacement field will have obvious frictional slip,and when the cycle reaches a certain number of times, the overall stick-slip phenomenon will occur. ② With the increase of the number of cycles,the displacement field has obvious space-time evolution characteristics with cyclic loading. There are obvious shear displacement increases and decreases in space,and there is obvious accumulation of displacement with the increase of the cycle number. It is re- presented by the zonality of displacement evolution and the cumulative effect of shear displacement field. There is hys- teresis of shear displacement evolution relative to shear stress in time. ③ Under the same shear stress level,as the number of cycles increases,the overall trend of vertical displacement decreases,the degree of interface occlusion in- creases,the horizontal sliding displacement increases,the interface partition sliding mechanism changes,and the load- ing end and the free end have obvious sticky sliding phenomenon. ④ Before and after the overall viscosity-slip of the specimen,the shear displacement varies with the increase of cycle times. Before stick-slip,the shear displacement in- creases slowly with the increase of the number of cycles. After stick-slip,the shear displacement increases obviously with the increase of the number of cycles. That is,before and after viscous slip,the interface slip rate increases slowly.

国家自然科学基金资助项目(51274207);国家自然科学基金青年基金资助项目(50904071)

YANG Xiaobin,ZHOU Jie,SONG Yimin,et al. Evolution characteristics of sliding displacement of rock interface under cyclic loading[J]. Journal of China Coal Society,2019,44(10):3041-3048.