胶结充填体冲击破坏及损伤演化数值模拟研究  

Numerical Simulation Research on Impact Failure and Damage Evolution of Cemented Backfill

作　　者：李祥龙[1,2] 李强 王建国[1,2] 杨长辉[1] 陶子豪 左庭 赵泽虎 LI Xianglong;LI Qiang;WANG Jianguo;YANG Changhui;TAO Zihao;ZUO Ting;ZHAO Zehu(Faculty of Land Resources Engineering,Kunming University of Science and Technology,Kunming,Yunnan 650093,China;New Blasting Technology Engineering Research Center of Yunnan Provincial Education Department,Kunming,Yunnan 650093,China)

机构地区：[1]昆明理工大学国土资源工程学院,云南昆明650093 [2]云南省教育厅爆破新技术工程研究中心,云南昆明650093

出　　处：《北京理工大学学报》2022年第7期733-740,共8页Transactions of Beijing Institute of Technology

基　　金：国家自然科学基金重点资助项目(51934003);国家自然科学基金地区基金资助项目(52064025);云南省基础研究计划面上项目(202201AT070178)。

摘　　要：为定量描述胶结充填体在动载作用下的损伤程度及破坏过程,利用数值模拟软件对胶结充填体进行SHPB动态冲击,并通过室内SHPB冲击试验结果验证数值模拟方法的可行性.对不同冲击速度(1.5,1.7,1.8,2.0 m/s)条件下4种配比胶结充填体(灰砂质量比分别为1∶4,1∶6,1∶8,1∶10),采用微裂纹密度法定义损伤变量值d,进行损伤规律及破坏过程的数值模拟研究.结果表明:数值模拟中使用波形整形器可获得更加理想的矩形波,使试件同一平面单元所受应力均匀,无应力集中现象;数值模拟结果很好地展现了胶结充填体的动态破坏过程,其整体破坏趋势为边缘发生剥落后裂纹向内部延伸与贯穿;在加载速度从1.7 m/s增加至1.8 m/s的过程中,损伤变量增大幅度超过10%;冲击速度由1.5 m/s增加至2.0 m/s的过程中,灰砂质量比为1∶4,1∶6,1∶8和1∶10的胶结充填体的损伤变量d变化范围分别为0.238~0.336,0.274~0.413,0.391~0.547,0.473~0.617,灰砂质量比1∶6变化至1∶8时,出现明显的损伤“跃升”现象.In order to quantitatively describe the damage degree and failure process of the cemented backfill under dynamic load,numerical simulation software was used to perform SHPB dynamic impact on the cemented backfill,and the feasibility of the numerical simulation method was verified by the indoor SHPB impact test results.For 4 kinds of cemented fillings(with cement-sand mass ratios of 1∶4,1∶6,1∶8 and 1∶10 respectively)made under different impact speeds(1.5,1.7,1.8,and 2.0 m/s),the micro-crack density method was used to define the damage variable value d,and a numerical simulation study of the damage law and the failure process was conducted.The results are as follows.The wave shaper can be used in the numerical simulation to obtain a more ideal rectangle wave,making the stress on the same plane element of the specimen uniform without stress concentration.The numerical simulation results show the dynamic failure process of the cemented filling body,and the overall failure trend is that the edge peels off and the crack extends to the inside.In the process of increasing the loading speed from 1.7 m/s to 1.8 m/s,the damage variable increases by more than 10%;during the process of increasing the impact speed from 1.5 m/s to 2.0 m/s,the variation ranges of the damage variable d of the cemented filling body with the cement-sand mass ratios of 1∶4,1∶6,1∶8 and 1∶10 are 0.238~0.336 0.274~0.413, 0.391~0.547, and 0.473~0.617, respectively. When the lime-to-sand ratio changes from 1:6 to 1:8, the damage “jumps” remarkably.

关 键 词：SHPB实验数值模拟 动态加载 胶结充填体 动态破碎过程 损伤演化 

分 类 号：TU45[建筑科学—岩土工程]