摘要
以川藏铁路沿线位于理塘-德巫断裂带附近的典型基覆型边坡为原型,基于相似准则,按与原型相似比1∶10设计模型,进行汶川卧龙地震波、Kobe地震波、El Centro地震波作用下边坡地震坍塌试验,利用位移响应及加速度的HHT(Hilbert-Huang Transform)谱进行边坡在地震作用下的变形和破坏特征研究。结果表明:边坡坍塌过程可分为稳定振动、裂缝扩张和坍塌破坏3个阶段;稳定振动阶段边坡内力可抵消大部分地震动能量,土体内部出现少量弹性位移,不同地震波类型造成的边坡HHT谱幅值有明显差异,且主要为低频振动;裂缝扩张阶段边坡坡面出现碎屑流,土体产生明显塑性变形;坍塌破坏阶段边坡坍塌为局部效应,坍塌相邻区域的HHT谱幅值在时域上分布较大,坍塌时伴随出现软弱夹层面的滑坡,坡面位移大小与不同地震波作用下的HHT谱幅值大小保持对应。
Based on the similarity criterion,the slope model was designed according to the similarity ratio of 1:10 to the prototype for the typical overburden layer slope near Litang-Dewu fault zone along Sichuan-Tibet Railway.The seismic collapse tests of the slope were carried out under Wenchuan-Wolong seismic wave,Kobe seismic wave and El Centro seismic wave.The HHT(Hilbert-Huang Transform)spectrum of displacement response and acceleration was used to study the deformation and failure characteristics of the slope under earthquake.The results show that the slope collapse can be divided into three stages:stable vibration,crack expansion and collapse failure.In the stable vibration stage,the internal force of the slope can counteract most of the ground motion energy and a small amount of elastic displacement occurs in the soil.The HHT spectrum amplitudes of the slope caused by different types of seismic waves are obviously different,and are mainly lowfrequency vibrations.In the crack expansion stage,the debris flow appears on the slope surface and the soil mass produces obvious plastic deformation.In the collapse failure stage,the slope collapse is a local effect,and the HHT spectrum amplitude of the collapse adjacent region is widely distributed in the time domain.The collapse is accompanied by a landslide with weak interlayer,and the displacement magnitudes of the slope correspond to those of HHT spectrum amplitudes under different seismic waves.
作者
杨长卫
童心豪
蔡德钩
张良
瞿立明
郭雪岩
YANG Changwei;TONG Xinhao;CAI Degou;ZHANG Liang;QU Liming;GUO Xueyan(School of Civil Engineering,Southwest Jiaotong University,Chengdu Sichuan 610031,China;Railway Engineering Research Institute,China Academy of Railway Sciences Corporation Limited,Beijing 100081,China)
出处
《中国铁道科学》
EI
CAS
CSCD
北大核心
2021年第5期12-20,共9页
China Railway Science
基金
国家重点研发计划项目(2018YFE0207100)
国家自然科学基金资助项目(52078426)
四川省科技计划项目(2020YJ0253)
中铁二院工程集团有限责任公司科研项目(KYY2019145(19–20))。
关键词
边坡
坍塌
地震作用
HHT
振动台试验
Slope
Collapse
Earthquake effect
HHT
Shaking table test
