被动围压下黄土动态力学性能与能量耗散研究  

Research on dynamic properties and energy dissipation of loess under passive confining pressure conditions

作　　者：熊仲明 吕世鸿[1,3] 李运良 赵奇峰[3] 李进[3] 谭书舜[3] 张向荣[3] 朱玉荣[3] 姜磊[2,3] 杨琪凡[3,4] 张宁波 张子栋 XIONG Zhong-ming;LV Shi-hong;LI Yun-liang;ZHAO Qi-feng;LI Jin;TAN Shu-shun;ZHANG Xiang-rong;ZHU Yu-rong;JIANG Lei;YANG Qi-fan;ZHANG Ning-bo;ZHANG Zi-dong(XAUAT UniSA An De College,Xi'an University of Architecture and Technology,Xi'an,Shaanxi 710311,China;College of Civil Engineering,Xi'an University of Architecture and Technology,Xi'an,Shaanxi 710055,China;Northwest Institute of Nuclear Technology,Xi'an,Shaanxi 710024,China;College of Information and Control Engineering,Xi'an University of Architecture and Technology,Xi'an,Shaanxi 710055,China)

机构地区：[1]西安建筑科技大学安德学院,陕西西安710311 [2]西安建筑科技大学土木工程学院,陕西西安710055 [3]西北核技术研究所,陕西西安710024 [4]西安建筑科技大学信息与控制工程学院,陕西西安710055

出　　处：《岩土力学》2021年第3期775-782,789,共9页Rock and Soil Mechanics

基　　金：国家自然科学基金项目(No.11872318)。

摘　　要：为研究被动围压条件下黄土的动态力学性能与能量耗散规律,利用Φ100 mm分离式霍普金森压杆(SHPB)试验装置对不同初始密度的黄土试样开展了不同冲击速度的动态压缩试验。通过应力平衡和常应变率分析对试验结果的有效性进行了验证,得到了黄土试样动态应力-应变曲线与吸收能变化时程曲线。试验结果表明:应变率在330~620s^(-1)范围内时,初始密度为1.7 g/cm^(3),含水率为4.45%的黄土试样屈服强度受应变率影响较小,应变率效应不明显;应变率在445 s^(-1)左右时,含水率为3.77%的黄土试样屈服强度、动态峰值应力比与能量吸收随试样初始密度的增大而增大;入射能在1700~5500 J范围内时,初始密度为1.7 g/cm^(3),含水率为4.45%的黄土试样能量耗散率在27%左右,比能量吸收随入射能的增大而增大。试验结果可为有关黄土的军事及民用工程的建设与防护提供技术参考。In order to investigate the dynamic properties and energy dissipation of loess under passive confining pressure condition,aΦ100 mm split Hopkinson pressure bar(SHPB)apparatus was used to conduct dynamic compression tests on loess samples with different initial densities at different impact speeds.The validity of the experiment was verified by considering the stress equilibrium and constant strain rate,the dynamic stress-strain curve and absorbed energy time history curve of the loess sample were obtained.Experimental results show that when the strain rate is in the range of 330~620 s^(-1),the yield strength of the loess sample with the initial density of 1.7 g/cm^(3)and the moisture content of 4.45%is less affected by the strain rate,and the strain rate effect is not obvious.When the strain rate is about 445 s^(-1),the yield strength,dynamic peak stress and specific energy absorption of the loess sample with a moisture content of 3.77%increase with the increase of the initial density of the sample.In the incident energy range of 1700~5500 J,the energy dissipation rate of the loess sample with the initial density of 1.7 g/cm^(3)and the moisture content of 4.45%is about 27%,and the specific energy absorption increases with the increase of incident energy.The test results can provide technical reference for the construction and protection of military and civil engineering construction related to loess.

关 键 词：黄土 SHPB 动态力学性能 能量耗散 应变率 密度 

分 类 号：TU444[建筑科学—岩土工程]