动载作用下复合岩体力学失稳机制与损伤本构模型研究  

Instability mechanism and damage constitutive model of composite rock mechanics under dynamic load

作　　者：吉东亮 高新强[1] 董北毅 高璐[2] 赵旭晨 马怡琛 刘禹辛 JI Dongliang;GAO Xinqiang;DONG Beiyi;GAO Lu;ZHAO Xuchen;MA Yichen;LIU Yuxin(State Key Laboratory of Mechanical Behavior in Traffic Engineering Structure and System Safety,Shijiazhuang Tiedao University,Shijiazhuang 050043,China;School of Energy and Mining Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China)

机构地区：[1]石家庄铁道大学省部共建交通工程结构力学行为与系统安全国家重点实验室,河北石家庄050043 [2]中国矿业大学(北京)能源与矿业学院,北京100083

出　　处：《振动与冲击》2024年第19期103-116,共14页Journal of Vibration and Shock

基　　金：河北省教育厅青年基金(50199990574);河北省省级科技计划资助(225676162GH)。

摘　　要：为探究不同层理倾角复合岩体的动载响应特性,利用WDW-300E伺服压力试验机和分离式霍普金森压杆(split Hopkinson pressure bar,SHPB)试验系统对不同层理倾角的复合岩体进行压缩试验和动态冲击试验,基于静载结果对比了动力冲击下复合岩煤(rock coal,R-C)和复合煤岩(coal rock,C-R)的动态强度、能量耗散以及破坏模式。考虑到介质弹性模量和强度的非均质性,通过二次开发得到弹性损伤本构模型,最后建立了考虑复合岩体宏细观损伤的本构模型。试验、模拟和理论分析结果表明:在静载条件下随着层理角度的增加,复合岩体应力峰值表现出明显倒U型变化,其弹性模量逐渐增加而峰值应变在逐渐减小。动载作用下复合岩体R-C和C-R峰值应力、应变和能量耗散值随着角度的增加均表现为先减小后增大,复合岩体R-C的应力、能量耗散值和弹性模量值大于复合岩体C-R,而复合岩体R-C的应变值普遍小于复合岩体C-R。在动载冲击作用下复合岩体在层理倾角为0°和90°时破坏形式主要为劈裂拉伸,吸能率较高破碎块度相对较小,在30°、45°和60°则主要为剪切和拉伸混合破坏,吸能率较低破碎块度相对较大。利用弹性损伤本构模型再现了不同层理倾角下复合岩体内部损伤过程和能量演化。构建了同时考虑复合岩体宏细观损伤的本构模型,其与试验和模拟结果均可以较好地吻合,验证了构建模型的正确性。Here,to investigate dynamic response characteristics of composite rock masses with different bedding angles,compression tests and dynamic impact tests were conducted for composite rock masses with different bedding angles using WDW-300E servo pressure testing machine and split Hopkinson pressure bar(SHPB)testing system.Based on static load results,dynamic strength,energy dissipation and failure modes of composite rock coal(R-C)and composite coal rock(C-R)under dynamic impact were compared.Considering the heterogeneity of elastic modulus and strength of medium,the elastic damage constitutive model was obtained with secondary development,and finally the constitutive model considering macro and micro damages of composite rock masses was established.The results of test,simulation and theoretical analysis showed that under static load condition,with increase in bedding angle,peak stress of composite rock mass has an obvious inverted U-shaped change,its elastic modulus gradually increases while peak strain gradually decreases;under dynamic load condition,peak stress,strain and energy dissipation values of composite rock mass R-C and C-R all decrease firstly and then increase with increase in bedding angle;stress,energy dissipation and elastic modulus of composite rock mass R-C are larger than those of composite rock mass C-R,while strain of composite rock mass R-C is generally smaller than that of composite rock mass C-R;under dynamic load impact,failure mode of composite rock mass is mainly splitting and stretching when the bedding angle is 0°and 90°,energy absorption rate is higher and fragmentation degree is relatively smaller;when the bedding angle is 30°,45°and 60°,failure mode of composite rock mass is mainly a mixed failure of shear and tension,the energy absorption rate is lower and fragmentation degree is relatively larger;the elastic damage constitutive model is used to reproduce internal damage process and energy evolution of composite rock masses under different bedding angles;the constitutive model co

关 键 词：复合岩体 层理角度 动载破坏 本构开发 宏细观损伤 

分 类 号：TH212[机械工程—机械制造及自动化]