动静加载条件下泥岩蠕变及细观破裂机制分析  

Mudstone creep experiment and mesomechanical analysis of failure mechanism under cyclic disturbance load and static load

作　　者：王俊光[1] 杨鹏锦 金峤 WANG Junguang;YANG Pengjin;JIN Qiao(School of Mechanics&Engineering,LiaoningTechnical University,Fuxin,Liaoning123000,China)

机构地区：[1]辽宁工程技术大学力学与工程学院

出　　处：《中国矿业大学学报》2019年第6期1223-1229,共7页Journal of China University of Mining & Technology

基　　金：国家自然科学基金项目(51404130);国家重点研发计划项目(2016YFC0600704);辽宁省自然科学基金项目(20180550708)

摘　　要：为了研究动静组合加载下泥岩蠕变特性及破裂机制,采用自行研制的岩石扰动蠕变试验台对不同扰动条件下的泥岩进行单轴压缩蠕变试验,并对泥岩蠕变破坏断口进行电镜扫描,研究了不同扰动幅值和频率对泥岩蠕变及断口细观特征的影响.结果表明:随着轴压的增加,扰动载荷对泥岩蠕变特性的影响更显著;扰动幅值和扰动频率越大,泥岩蠕变破坏时间越短,极限应变值越大;随着扰动幅值的增加,断口形貌由韧性断裂和脆性断裂耦合转变为脆性断裂为主,宏观破裂表现为劈裂破坏;随着扰动频率的增加,岩石内部逐渐出现疲劳断口形貌,裂纹从晶体内部发育,岩石宏观破坏越严重,裂隙发育更为丰富.The creep characteristics and fracture mechanism of mudstone under dynamic and static combined loading were obtained by uniaxial compression creep test of mudstone under different disturbance conditions on a self-developed rock disturbance creep test-bed.The influence of different disturbance amplitudes and frequencies on creep and fracture characteristics of mudstone was studied by scanning electron microscopy.The results show that with the increase of axial compression, the influence of disturbance load on creep characteristics of mudstone is more significant.The larger the disturbance amplitude and frequency, the shorter the creep failure time of mudstone and the larger the ultimate strain value.With the increase of disturbance amplitude, the fracture morphology changes from coupling of ductile fracture and brittle fracture to brittle fracture, and the macroscopic fracture of rock shows splitting failure.With the increase of disturbance frequency, fatigue fracture gradually appears in the rock. Meanwhile,cracks develop from the inside of the crystal, the macroscopic damage of rock is more serious, and the development of cracks is more abundant.

关 键 词：扰动蠕变 扰动幅值 扰动频率 电镜扫描 细观破坏机制 

分 类 号：TU452[建筑科学—岩土工程]