近断层地震动对阶梯式顺层岩质路堑边坡震裂损伤的作用机制  

Action mechanism of near-fault earthquake on shatter damage of stepped bedding rock cutting slope

作　　者：信春雷 李文惠 冯文凯[1,3] 杨飞 廖军[3] XIN Chunlei;LI Wenhui;FENG Wenkai;YANG Fei;LIAO Jun(State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu University of Technology,Chengdu 610059,China;Department of Architecture and Civil Engineering,Sichuan Vocational and Technical College of Communications,Chengdu 611130,China;College of Environment and Civil Engineering,Chengdu University of Technology,Chengdu 610059,China)

机构地区：[1]成都理工大学地质灾害防治与地质环境保护国家重点实验室,四川成都610059 [2]四川交通职业技术学院建筑工程系,四川成都611130 [3]成都理工大学环境与土木工程学院,四川成都610059

出　　处：《振动工程学报》2025年第2期352-364,共13页Journal of Vibration Engineering

基　　金：国家自然科学基金资助项目(52108361,41977252);四川省科技厅重点研发项目(23ZDYF2234);地质灾害防治与地质环境保护国家重点实验室自主课题和开放基金资助项目(SKLGP2020Z001,SKLGP2020K018)。

摘　　要：中国西南部特殊的地形条件导致公路交通建设中不可避免地形成大量路堑边坡,地震作用下公路路堑边坡的稳定性问题俨然成为公路工程稳定性研究中的重点科学问题。通过大型振动台试验分析阶梯式顺层岩质路堑边坡的加速度响应,研究边坡各平台的地震动响应规律。提出加速度放大系数比表征不同坡表形式的动力响应差异,结合Snell定律分析地震波在边坡中的传播规律。结果表明:边坡加速度放大系数随激振幅值增加而表现出高程放大效应,当激振幅值超过0.6g时,因震裂损伤累积,坡体滤波效应增强,加速度放大系数随高程增长趋于平缓。均匀阶梯宽度的边坡抗震性能较好,阶梯阴角处易产生应力集中,应作为重点防护区域。试验中监测的加速度数据分析结果与高速摄像机记录的模型损伤结果相吻合。根据边坡的震裂累积破坏过程,可将破坏现象分为浅层蠕滑(0.1g~0.4g)、局部拉裂(0.4g~0.6g)、加速变形(0.6g~0.8g)和整体失稳(0.8g~1.0g)四个发展阶段,变形破坏模式总体表现为滑移-拉裂式。研究结果为复杂坡面与地质结构的震裂破坏机制及抗震设防提供了理论基础和技术支持,为山区阶梯式岩质路堑边坡的防灾减灾措施提供参考。In the southwest region of China,the construction of highways has resulted in the formation of many cutting slopes due to the special terrain conditions of the region.Therefore,the stability of highway cutting slopes under earthquake conditions has be-come a critical issue in the stability evaluation of highway engineering.In this research,the acceleration response of stepped bed-ding rock slopes is analyzed by conducting large-scale shaking table tests,and the seismic response of each platform is investigated.A ratio of acceleration amplification factor is proposed to characterize the differences in dynamic responses of various slope patterns and analyzes the seismic wave propagation in the slope using Snell’s law.The test reveals that the acceleration amplification factor of the slope exhibits an elevation amplification effect as the amplitude of the excitation increases.When the excitation amplitude ex-ceeds 0.6g,the continuous accumulation of slope shattering damage and the enhancement of the filtering effect lead to a leveling off of the acceleration amplification factor with increasing elevation.Besides,slopes with uniform step width demonstrate better aseis-mic performance,while stress concentration is more likely to occur at the corners of each step,making them as key fortification sites.The analysis of the monitored acceleration data is consistent with the model damage patterns recorded by a high-speed camera during the shaking table tests.Based on the cumulative shattering damage process of the slope,four stages of damage are identi-fied:shallow creep(0.1g~0.4g),local tension(0.4g~0.6g),accelerated deformation(0.6g~0.8g),and overall instability(0.8g~1.0g),exhibiting a slip-tensile damage mode.The research findings provide essential theoretical support and technical guid-ance for understanding the shattering damage mechanism and seismic fortification of rock slopes with complex formations and geo-logical structures,and offer a reference for disaster prevention and mitigation measures for stepped beddin

关 键 词：边坡工程 阶梯式岩质边坡 振动台试验 Snell定律 震裂损伤模式 

分 类 号：TU435[建筑科学—岩土工程]