摘要
为研究不同夹层材料下软硬介质组合岩体的动态力学性能及变形破坏特征,以砂岩和花岗岩为软硬岩基质,利用分离式霍普金森压杆(split Hopkinson pressure bar,SHPB)装置,并通过离散格子弹簧法(discrete lattice spring method,DLSM)数值模拟,探究了不同夹层材料下岩体裂纹扩展、夹层界面处的反、透射特性及岩体中能量分配特性。结果表明:不同夹层材料岩体的动态强度增长因子随着岩体动态抗压强度增大而增大,表现出明显的动态抗压强度依赖性。不同夹层材料岩体在加载初始阶段存在明显的非线性段,无夹层岩体砂岩内部闭合的孔隙及裂隙在应力开始作用阶段最久且非线性段最长。随着夹层材料强度的增大,夹层对岩体的裂纹扩展和发育的阻碍能力逐渐较弱,岩体产生裂纹和破坏需要消耗的能量逐渐降低。夹层岩体的破坏开始于夹层胶结面处,随着夹层材料强度的增大,软岩靠近胶结面一侧破坏逐渐加剧,硬岩无明显破坏。含夹层岩体具有很好的削波作用,随着夹层材料强度的降低,两端面应力峰值在逐渐降低,夹层岩体短时间内获得的能量吸收密度增大,稳定性降低,容易被破坏。
A split Hopkinson pressure bar(SHPB)device was used to study the dynamic mechanical properties and deformation and failure characteristics of the rock mass combined with different sandwich materials,using sandstone and granite as the soft and hard rock matrix.The discrete lattice spring method(DLSM)was used to further investigate the crack propagation,the reaction and transmission at the interlayer interface and the energy distribution characteristics of rock mass combined with different interlayer materials.The results show that the growth factor of rock mass dynamic strength increases with the increase of rock mass dynamic compressive strength,showing an obvious dynamic compressive strength dependence.The rock mass combined with different interlayer materials has a obvious nonlinear section in the initial loading stage,and the closed pores and cracks in the sandstone of non-interlayer rock have the longest nonlinear section in the initial stress stage.With the increase of the strength of interlayer material,the obstacle ability of interlayer to crack propagation and development of rock mass gradually becomes weak,and the energy consumption of rock mass crack and failure is gradually reduced.The failure of the intercalated rock mass starts at the cementation surface of the intercalated rock mass.With the increase of the strength of the intercalated material,the failure of the soft rock near the cementation surface is gradually intensified,while the hard rock has no obvious failure.The rock mass with interlayer has a good clipping effect.With the decrease of the strength of interlayer material,the peak stress value of both ends gradually increases and decreases,whilst the energy absorption density of the interlayer rock mass increases in a short time,and the stability becomes worse,so it is easy to be destroyed.
作者
王雁冰
宋佳辉
任斌
刘珍
龙永东
WANG Yanbing;SONG Jiahui;REN Bin;LIU Zhen;LONG Yongdong(School of Mechanics and Civil Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China;State Key Laboratory of Geomechanics and Deep Underground Engineering,China University of Mining and Technology(Beijing),Beijing 100083,China)
出处
《爆炸与冲击》
EI
CAS
CSCD
北大核心
2023年第12期12-24,共13页
Explosion and Shock Waves
基金
国家重点研发计划(2021YFC2902103)
国家自然科学基金(51934001)
中央高校基本科研业务费专项资金(2023JCCXLJ02)。
关键词
夹层材料岩体
裂纹扩展
SHPB
离散格子弹簧法
intercalated rock mass
crack propagation
SHPB
discrete lattice spring method
