组合倾角对软硬介质组合岩体动态力学特性的影响
Effect of combined dip angle on dynamic mechanical properties of combined rock mass with hard and soft media
王雁冰 1宋佳辉 1杨柳 1邹宝平 2任斌 1李林青1
作者信息
- 1. 中国矿业大学(北京)力学与土木工程学院,北京 100083
- 2. 浙江科技大学土木与建筑工程学院,浙江杭州 310023
- 折叠
摘要
为探究冲击荷载下不同组合倾角软硬介质组合岩体的动力学响应特性,利用分离式霍普金森压杆(SHPB)、高速相机和离散格子弹簧法(DLSM)数值模拟,对花岗岩-砂岩6种不同组合倾角软硬介质组合岩体进行动态冲击试验,研究6种不同组合倾角软硬介质组合岩体的应力波传播特征、应力-应变曲线差异、能量耗散规律、损伤演化特性以及总动能同岩体裂纹扩展之间的关系.结果表明:软硬介质组合岩体的动态力学特性及能量耗散规律均与组合倾角相关.组合倾角由0°增加至75°时,试件透射波幅值、峰值应力、动态弹性模量呈先增大后减小的变化趋势,反射波幅值呈先减小后增大的变化趋势.组合倾角为45°～60°,软硬介质组合岩体容易被破坏.组合倾角不仅会阻碍应力波传播也会影响胶结面两侧岩石的应力变化,使胶结面两侧岩体产生二次加载现象.岩体的损伤值随组合倾角增加呈倒"V"型变化,45°～60°范围内试件的损伤值最高.组合倾角越大,岩体破坏过程中总动能越低,裂纹则越少,试件的变形位移量越小.
Abstract
In order to explore the dynamic response characteristics of the rock mass with different combined dip angles under impact load,the dynamic impact tests of the rock mass with six different combined dip angles of granite and sandstone were carried out by using the separated Hopkinson pressure bar(SHPB),high-speed camera and discrete lattice spring method(DLSM).The stress wave propagation characteristics,stress-strain curve difference,energy dissipation law,damage evolution characteristics and the relationship between total kinetic energy and crack propagation of rock mass with six different combination dip angles were studied.The results show that the dynamic mechanical properties and energy dissipation law of the combined rock mass are related to the combined dip angle.When the combined dip angle increases from 0° to 75 °,the transmitted wave amplitude,peak stress and dynamic elastic modulus of the specimen increase first and then decrease,while the reflected wave amplitude decreases first and then increases.When the combined dip angle is in the range of 45°-60°,the combined rock mass of hard and soft medium is easy to be destroyed.Combined dip angle will not only hinder the stress wave propagation but also affect the stress change of rock on both sides of the bonding surface,resulting in secondary loading phenomenon of rock on both sides of the bonding surface.The damage value of rock mass presents an inverted"V"shape with the increase of combination dip angle,and the damage value is the highest in the range of 45 °-60°.The larger the combined dip angle is,the lower the total kinetic energy in the rock mass failure process,the less cracks,and the smaller the deformation and displacement of the specimen.
关键词
岩石力学/组合倾角/组合岩体/分离式霍普金森压杆/能量耗散/离散格子弹簧法Key words
rock mechanics/combined dip angle/combinatorial rock mass/separated Hopkinson pressure bar(SHPB)/energy dissipation/discrete lattice spring method(DLSM)引用本文复制引用
基金项目
国家重点研发计划(2021YFC2902103)
国家自然科学基金重点项目(51934001)
中国矿业大学(北京)越崎青年学者资助项目(800015Z11A24)
出版年
2024
NETL
NSTL
万方数据