摘要
顺倾层状边坡沿软弱带剪切方式破坏是滑坡的主要类型之一。采用块体砌筑斜坡振动台模型,在多维多参数地震动作用下,考虑斜坡不同工况下力学参数弱化的过程,研究了层状碎裂结构岩质边坡的地震动力响应和失稳破坏模式。结果表明:斜坡地震动特性和斜坡地质结构是决定斜坡地震动力稳定性以及破坏模式的决定因素;斜坡水平动力响应具有明显的高程和坡表放大效应,高程对斜坡的垂直动力响应影响较小,地震动放大效应与结构面力学强度、地震波波形、频谱特性等均有一定的关系,正弦波较天然波对坡体放大效应影响更为显著;坡体裂纹依托优势结构面在最弱部位起裂萌生扩展,并向节理面追踪形成蠕滑段和锁固段,节理面强度参数在外界地质营力作用下发生弱化,使潜在滑带出现由后缘向前端搭接贯通的前进式破坏模式和由前端向后缘的后退式破坏模式的分化,滑体也由高位剪出向溃散破坏演变。
Shear failure of bedding slope along weak zone is one of the main types of landslides.The seismic dynamic response and destabilization failure mode of rock slopes with laminated fractured structure were studied by a shaking table model of block masonry slope under the action of multi-dimensional and multi-parameter ground motion,meanwhile,considering the weakening process of mechanical parameters of slope under different working conditions of slopes.The results show that the ground shaking characteristics and geological structure of the slope are the decisive factors to determine the seismic dynamic stability and failure mode of the slope.The horizontal dynamic response of the slope has obvious elevation and slope surface amplification effects,and the elevation has less influence on the vertical dynamic response of the slope.Ground motion amplification effect is related to the mechanical strength of the structural surface,the waveform of seismic waves,and the spectral characteristics,and the sine wave has a more significant influence on the amplification effect of the slope than the natural wave.The slope cracks initiate and expand at the weakest part depending on the dominant structural surface and trace to the joint surface to form creep-slip and locking sections.The strength parameter of the joint surface weakens under the action of the external geological agents so that the potential slip zone appears to be differentiated between the forward failure mode of lap penetration from the rear edge to the front and the backward failure mode from the front to the rear edge,and accordingly the slip mass also evolves from shear exposure at high position to collapse failure.
作者
许明
余小越
赵元平
胡家驹
张潇婷
XU Ming;YU Xiao-yue;ZHAO Yuan-ping;HU Jia-ju;ZHANG Xiao-ting(School of Civil Engineering,Chongqing University,Chongqing 400045,China;National Joint Engineering Research Center of Geohazards Prevention in the Reservoir Areas,Chongqing University,Chongqing 400045,China;CISDI Engineering Co.,Ltd.,Chongqing 400013,China;China Construction Fifth Engineering Division Co.,Ltd.,Changsha,Hunan 410004,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2023年第2期362-372,共11页
Rock and Soil Mechanics
基金
国家自然科学基金(No.52279094,No.51478065)
广西重点研发计划(桂科AB20238036)。
关键词
顺层岩质边坡
砌块模型
振动台试验
地震动参数
动力响应
破坏模式
bedding rock slope
block model
shaking table test
seismic ground motion parameters
dynamic response
failure mode
作者简介
第一作者:许明,男,1975年生,博士,教授,主要从事岩土工程领域的研究。E-mail:foretech@163.com;通讯作者:余小越,女,1998年生,硕士研究生,主要从事岩土工程领域的研究。E-mail:sweetmoonlet@163.com。
