高径比差异条件下花岗岩岩石动态冲击压缩特性  

Dynamic impact compression characteristics of granite rocks with different length-diameter ratios

作　　者：赵光明[1,2] 周俊[1,2] 孟祥瑞[1,2] 考四明[1,2] 张若飞[1,2] 黄顺杰 ZHAO Guangming;ZHOU Jun;MENG Xiangrui;KAO Siming;ZHANG Ruofei;HUANG Shunjie(State Key Laboratory of Deep Coal Mine Mining Response and Disaster Prevention and Control,Anhui University of Science and Technology,Huainan,Anhui 232000,China;School of Mining Engineering,Anhui University of Science and Technology,Huainan,Anhui 232000,China)

机构地区：[1]安徽理工大学深部煤矿采动响应与灾害防控国家重点实验室,安徽淮南232000 [2]安徽理工大学矿业工程学院,安徽淮南232000

出　　处：《岩石力学与工程学报》2021年第7期1392-1401,共10页Chinese Journal of Rock Mechanics and Engineering

基　　金：国家自然科学基金资助项目(51974009);安徽省重点研究与开发计划项目(201904a07020010);安徽省“省特支计划”的领军人才项目。

摘　　要：为研究动态冲击下岩石强度尺寸效应,设计高径比分别为0.5,0.6,0.7,0.8,0.9,1.0,1.2,1.5和2.0的9组花岗岩试样,利用Φ50 mm分离式霍普金森杆(SPHB)对花岗岩试样在3组冲击速度下进行动态冲击压缩试验。研究不同高径比的花岗岩试样产生破坏的力学特性,并对破碎后岩样进行吸收能分析。研究结果表明:在3组冲击速度加载下,不同高径比试样的抗压强度最大相差分别为10.88%,3.95%和8.17%;同一冲击速度,抗压强度不随高径比变化而发生明显变化;岩样高径比与峰值应变呈负相关,拟合数据曲线得出两者存在一定的非线性关系;试样高径比与弹性变形模量呈正相关,拟合数据曲线得出两者存在良好的线性关系。动态压缩不同高径比的岩样,其破坏形态有区别,破坏形式基本一致;入射能大小与冲击速度有关,与岩样高径比无关;反射能和透射能与岩样高径比拟合曲线规律相反;岩样破碎的吸收能不随岩样高径比的变化而发生显著变化,岩样单位长度破碎吸收能则随长度增加减小。In order to study the rock strength size effect under dynamic impact,nine groups of granite samples with different length-diameter ratios(0.5,0.6,0.7,0.8,0.9,1.0,1.2,1.5 and 2.0)were prepared,and dynamic impact compression tests were carried out under different impact speeds using Φ50 mm split Hopkinson bar(SPHB).The mechanical properties of granite specimens with different length-diameter ratios were studied,and the absorption energy of the broken specimens was analyzed.The results show that,under three impact velocity compression conditions,the maximum differences of the compressive strength of the samples with different length-diameter ratios are 10.88%,3.95%and 8.17%,respectively,and that,under the same impact velocity,the compressive strength does not change obviously with the change of the length-diameter ratio.The length-diameter ratio of the rock specimens is negatively correlated with the peak strain of the rock specimens,and the fitting data curve shows that there is a certain nonlinear relationship between them.The length-diameter ratio of the specimens is positively correlated with the elastic modulus,and the fitting data curve shows that there is a good linear relationship between them.The failure shapes of the rock specimens with different length-diameter ratios are different while the failure forms are basically the same.The magnitude of the incident energy is related to the impact velocity but independent of the length-diameter ratio of the rock specimens.The fitting curves between the reflected energy and the transmitted energy with the length-diameter ratio are contrary.The absorbed energy of rock specimen breakage does not change significantly with the length-diameter ratio,but the absorbed energy per unit length of rock specimen breakage decreases with increasing the length.

关 键 词：岩石力学 强度尺寸效应 高径比 花岗岩 力学特性 吸收能 

分 类 号：TU45[建筑科学—岩土工程]