Experimental and numerical investigations on the tensile mechanical behavior of marbles containing dynamic damage  

作　　者：Tao Zhang Liyuan Yu Haijian Su Qiang Zhang Shaobo Chai 

机构地区：[1]State Key Laboratory for Geomechanics and Deep Underground Engineering,China University of Mining and Technology,Xuzhou 221116,China [2]School of Civil Engineering,Chang’an University,Xi’an 710064,China

出　　处：《International Journal of Mining Science and Technology》2022年第1期89-102,共14页矿业科学技术学报（英文版）

基　　金：financial support of the International Science and Technology Cooperation Plan of Jiangsu Province,China(No.BZ2020066);the National Natural Science Foundation of China(Nos.52179118,42077240 and 52074269)。

摘　　要：To investigate the degradation mechanism of static tensile mechanical behaviors of marble containing dynamic damage,multiple impact loading tests were performed on the disc marble samples,and then static Brazilian tests were conducted for the damaged samples.Besides,coupling modeling technology of finite difference method(FDM)—discrete element method(DEM)was used to carry out the numerical investigation.The results show that after multiple impacts,more white patches appear on the surface,and some microcracks,macro-fractures as well as pulverized grains are found by optical microscopic.The static tensile strength decreases with the increase of the dynamic damage variable characterized by the ultrasonic wave velocity of sample.The interaction between grains in the damaged sample becomes intense in the subsequent static loading process,causing a relatively large strain.The volume of the fragments falling off around the loading points becomes larger as impact number increases.As the dynamic damage increases,the absorbed energy of sample during the static loading first decreases and then tends to be stable.Both the stress concentration and the breakage of the force chains are the root causes of the degradation of the static tensile strength.

关 键 词：Rock mechanics Tensile mechanical behavior Cumulative dynamic damage SHPB FDM-DEM coupling 

分 类 号：TU45[建筑科学—岩土工程]