摘要
为了探究层理面影响下砂岩力学特性和破坏机理,采用声发射技术,开展砂岩单轴和巴西劈裂试验,研究砂岩拉压强度分布规律、应力应变关系、破坏形式与声发射之间的关系。研究结果表明:随着层理角度从0°增加至90°,砂岩单轴抗压强度先减小再增大,呈U型分布,而劈裂拉伸强度呈增大趋势;砂岩在单轴和劈裂试验下应力应变曲线具有明显的各向异性;在单轴试验下,当层理角度为0°,15°,75°和90°时,砂岩破坏形式为压缩破坏,当层理角度为30°,45°和60°时,砂岩破坏形式为沿弱面剪切破坏;在劈裂试验下,圆盘均沿着中心起裂破坏形式为拉伸破坏;随着层理角度从0°增加至90°,在单轴和劈裂试验下,裂纹发展所对应的轴向应变率降低,裂纹贯通困难,破坏所需峰值应力增大;峰值应力越大,对应的声发射能量率越大。
In order to investigate the mechanical properties and failure mechanism of layered rock mass under the influence of bedding plane,the acoustic emission technology was used to carry out the uniaxial and Brazil split tests of sandstone.The tensile and compressive strength distribution,relationship between stress and train,failure mode and acoustic emission of layered sandstone were studied.The results show that when the bedding angle increases from 0° to 90°,the uniaxial compressive strength of layered sandstone decreases first and then increases,showing a U-shaped distribution,while the tensile strength shows an increasing trend.Sandstone uniaxial and splitting test stress-strain curve have obvious anisotropy.During uniaxial test,compressive failure occurs when the bedding angles are 0°,15°,75° and 90°,and shear failure appears along the weak plane when the bedding angles are 30°,45° and 60°.During the splitting test,the tensile cracking of the center is ruined along the center.During the acoustic emission of uniaxial and splitting test,when the bedding angle increases from 0° to 90°,the axial strain rate corresponding to the crack development gradually decreases,and the more difficult the crack penetration,the higher the peak stress required for damage.The greater the peak stress,the greater the corresponding acoustic emission energy rate.
作者
刘运思
王世鸣
颜世军
傅鹤林
陈琛
史越
岳健
LIU Yunsi;WANG Shiming;YAN Shijun;FU Helin;CHEN Chen;SHI Yue;YUE Jian(Key Laboratory of Geotechnical Engineering for Stability Control and Health Monitoring of Hunan Province,Hunan University of Science and Technology,Xiangtan 411201,China;School of Civil Engineering,Hunan University of Science & Technology,Xiangtan 411201,China;School of Civil Engineering,Central South University,Changsha 410075,China)
出处
《中南大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2019年第6期1419-1427,共9页
Journal of Central South University:Science and Technology
基金
国家自然科学基金资助项目(51704109,51604109)
湖南省自然科学基金资助项目(2015JJ6038)
湖南省教育厅科学基金资助项目(16C0646)~~
关键词
岩石力学
层状砂岩
声发射
拉压力学特性
破坏机理
能量
rock mechanics
layered sandstone
acoustic emission
tension and compression characteristics
damage mechanism
energy
