一维动静组合加载下灰岩力学特性及能量耗散分析  

Analysis of Mechanical Properties and Energy Dissipation of Limestone under One-dimensional Dynamic and Static Combined Loading

作　　者：赵文环 陈剑 周泽卿 ZHAO Wenhuan;CHEN Jian;ZHOU Zeqing(Datun Tin Mine of Yunnan Tin Co.,Ltd.;Faculty of Land Resources Engineering,Kunming Univer-sity of Science and Technology)

机构地区：[1]云南锡业股份有限公司大屯锡矿 [2]昆明理工大学国土资源工程学院

出　　处：《现代矿业》2024年第5期235-239,共5页Modern Mining

摘　　要：为改善灰岩的破岩效率及能耗,采用分离式霍普金森压杆开展围岩一维动静组合加载试验研究,分析不同应变率、轴压梯度对灰岩的动态抗压强度、能量利用率以及破坏的影响。结果表明,当轴压一定时,灰岩试样在冲击荷载条件下的动态抗压强度随着应变率的增大呈线性增加趋势;相同应变率条件下,灰岩动态抗压强度随着轴压的增大而增大,但轴压超过一定的阈值之后,强度开始减小;不同轴压下灰岩的透射比率随着入射能的增加均呈现出指数减少趋势;轴压一定时,加载应变率越高,能耗密度越大,灰岩的变形越迅速,二者呈现出线性增加关系。在应变率相近的条件下,适当地增加轴压会使能耗密度明显降低,但过大轴压会加大能耗密度,因此破碎灰岩时,应考虑轴压和冲击荷载的综合作用。In order to improve the rock breaking efficiency and energy consumption of limestone,one dimensional dynamic and static combination loading tests of surrounding rock were carried out by separated Hopkinson pressure bar,and the effects of different strain rates and axial pressure gradients on the dynamic compressive strength,energy utilization and failure of limestone were analyzed.The results show that the dy⁃namic compressive strength of limestone specimens under impact load increases linearly with the increase of strain rate when axial pressure is constant.Under the same strain rate,the dynamic compressive strength of limestone increases with the increase of axial pressure,but the strength decreases when the axial pressure exceeds a certain threshold.The transmission ratio of limestone under different axial compression shows an exponential decreasing trend with the increase of incident energy.When axial pressure is constant,the high⁃er the loading strain rate is,the higher the energy consumption density is and the faster the deformation of limestone is.Under the condition of similar strain rate,the energy consumption density will be significantly reduced if the axial pressure is increased appropriately,but the energy consumption density will be in⁃creased if the axial pressure is too large.Therefore,the comprehensive effect of axial pressure and impact load should be considered when crushing limestone.

关 键 词：灰岩 一维动静组合 动态抗压强度 入射能 能耗密度 

分 类 号：TD313[矿业工程—矿井建设]