强震区抗滑桩加固碎石土边坡动力响应特征与桩身损伤识别:以川青铁路九寨沟双线大桥附近工点为例  

Dynamic Response Characteristics and Damage Identification of Pile Body of Gravel Soil Slope Strengthened by Anti-slide Pile in Strong Earthquake Area:Take Jiuzhaigou Double-line Bridge of Sichuan-Qing Railway as an Example

作　　者：王沛宇 吕润田 缪杰蔚 张崇磊[1,2] WANG Pei-yu;L Run-tian;MIAO Jie-wei;ZHANG Chong-lei(Key Laboratory of Mountain Hazards and Surface Processes,Institute of Mountain Hazards and Environment,CAS,Chengdu 610299,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院,水利部成都山地灾害与环境研究所山地灾害与地表过程重点实验室,成都610299 [2]中国科学院大学,北京100049

出　　处：《科学技术与工程》2024年第25期10910-10920,共11页Science Technology and Engineering

基　　金：国家自然科学基金区域创新发展联合基金(U22A20603);中国科学院、水利部成都山地灾害与环境研究所科研项目(IMHE-ZDRW-03)。

摘　　要：为掌握西南强震区服役抗滑桩的地震响应特征与损伤状态,基于川青铁路位于强震区典型工点,构建了地震作用下不同损伤状态抗滑桩加固碎石土边坡三维有限差分模型,研究了坡体的加速度响应、抗滑桩结构内力变化以及桩身初始损伤对坡体动力响应的影响;引入小波包能量谱法,基于桩身加速度响应数据,构建能量损伤判别指标对桩身进行损伤状态、损伤位置以及损伤程度的识别。结果表明,抗滑桩能有效降低桩身周围土体的加速度响应,坡体加速度总体表现为高程放大效应,滑面附近是桩身受力集中区域且桩身损伤会导致其抗弯、抗剪承载力下降,侧向水平位移增大,进而加剧坡体加速度响应。损伤判别指标D PERV沿桩身的分布特征能够有效识别抗滑桩的损伤位置和损伤程度,建立的桩顶残余位移、桩顶损伤指标D PERV与损伤程度三者之间的定量关系能够评估桩身相对损伤程度,为边坡工程中抗滑桩服役性能评价提供新的思路和方法。In order to grasp the seismic response characteristics and damage states of anti-slide piles in service in the strong earthquake area of southwest China,a three-dimensional finite difference model of anti-slide pile reinforced rubble soil slope under different damage states was constructed based on a typical site located in the strong earthquake area of Sichuan-Qing railway.The acceleration response of slope,the change of internal force of anti-slide pile structure and the influence of initial damage of pile body on the dynamic response of slope were studied.The wavelet packet energy spectrum method was introduced,and based on the acceleration response data of pile body,the energy damage discrimination index was constructed to identify the damage state,damage location and damage degree of pile body.The results show that the anti-slide pile can effectively reduce the acceleration response of the soil around the pile body,and the acceleration of the slope body generally presents an elevation amplification effect.The loading area near the sliding surface of the pile body is concentrated,and the damage of the pile body will lead to the decline of its flexural and shear bearing capacity and the increase of lateral horizontal displacement,which will further aggravate the acceleration response of the slope body.The distribution characteristics of damage discrimination index D PERV along the pile body can effectively identify the damage location and damage degree of anti-slide pile.The established quantitative relationship among pile top residual displacement,pile top damage index D PERV and damage degree can evaluate the relative damage degree of pile body,providing a new idea and method for evaluating the service performance of anti-slide pile in slope engineering.

关 键 词：抗滑桩 地震动力响应 小波包能量谱 损伤识别 数值模拟 

分 类 号：TU473[建筑科学—结构工程] P642[建筑科学—土工工程]