动静组合载荷致损后大理岩力学特性试验研究  

Experimental Study on Mechanical Properties of Marble After Damage Caused by Dynamic and Static Combined Loads

作　　者：赵奎[1,2] 闫泽亮 曾鹏[1,2] 杨道学[2] ZHAO Kui;YAN Zeliang;ZENG Peng;YANG Daorue(School of Resources and Environmental Engineering,Jiangxi University of Science and Technology,Ganzhou,Jiangxi 341000,China;School of Civil Engineering and Surveying&Mapping Engineering,Jiangxi University of Science and Technology,Ganzhou,Jiangxi 341000,China)

机构地区：[1]江西理工大学资源与环境工程学院,江西赣州市341000 [2]江西理工大学土木与测绘工程学院,江西赣州市341000

出　　处：《矿业研究与开发》2025年第3期128-136,共9页Mining Research and Development

基　　金：国家自然科学基金资助项目(52164004,52104086);江西省重点研发计划项目(20212BBG71009);江西省研究生创新专项资金项目(YC2022-S638)。

摘　　要：为研究动静组合载荷致损后大理岩的力学特性,利用改进的分离式霍普金森压杆装置对大理岩进行4个轴压水平(0、18 MPa、36 MPa、54 MPa)和3个冲击速度水平(8 m/s、9 m/s、10 m/s)下的动静组合载荷致损试验,对致损后的大理岩进行单轴压缩声发射试验。研究结果表明:动静组合作用下,随着轴向静压的增大,大理岩动态峰值应力、动态弹性模量、波速均呈先增大后减小的变化规律;吸收能与轴向静压密切相关,在轴向静压水平较低时,岩石内部微裂纹闭合所需能量主要从冲击杆中获得,随着轴向静压的增大,岩石从冲击杆中获得的能量占比逐渐减小;随着轴向静压的增大,动静组合载荷致损后岩石的单轴抗压强度和弹性模量均呈现先增大后减小的变化趋势,轴向静压为18 MPa时,岩石的单轴抗压强度和弹性模量达到最大值,适当的轴向静压能有效提高岩石抵抗动载荷的能力,减小岩石的损伤;单轴加载破坏过程中、后期,损伤程度小的岩石出现的声发射高频信号(>400 kHz)数量越少,中、低频声发射信号(165~205 kHz)数量越多。165~205 kHz的声发射信号占比在整个加载破坏过程中呈现先增大后减小的变化趋势,可将其作为岩石破坏的前兆特征。To study the mechanical properties of marble after damage caused by dynamic and static combined loads,the improved split Hopkinson pressure bar device was used to carry out dynamic and static combined load damage tests on marble at four axial compression levels(0,18 MPa,36 MPa,54 MPa)and three impact velocity levels(8 m/s,9 m/s,10 m/s).The uniaxial compression acoustic emission tests on the damaged marble was carried out.The results show that under the action of static and dynamic combination,with the increase of axial static pressure,the dynamic peak stress,dynamic elastic modulus and wave velocity of marble increase firstly and then decrease.The absorption energy is closely related to the axial static pressure.When the axial static pressure is low,the energy required for the closure of microcracks in the rock is mainly obtained from the impact bar.With the increase of axial static pressure,the proportion of energy obtained from the impact bar gradually decreases.With the increase of axial static pressure,the uniaxial compressive strength and elastic modulus of rock after damage caused by dynamic and static combined load increase firstly and then decrease.When the axial static pressure is 18 MPa,the uniaxial compressive strength and elastic modulus of rock reach the maximum value.Appropriate axial static pressure can effectively improve the ability of rock to resist dynamic load and reduce rock damage.In the middle and later stages of the uniaxial loading failure process,the less the number of high-frequency acoustic emission signals(>400 kHz)of the rock with small damage degree,the more the number of medium and low-frequency acoustic emission signals(165-205 kHz).The proportion of acoustic emission signals at 165-205 kHz increases firstly and then decreases during the whole loading process,which can be used as a precursory feature of rock failure.

关 键 词：动静组合载荷 力学特性 轴向静压 冲击速度 声发射信号 

分 类 号：TD313[矿业工程—矿井建设]