典型黄土场地简支梁桥桩-土相互作用抗震特性  

Seismic behavior of pile-soil interaction of simply supported beam bridges in a typical loess site

作　　者：叶晨阳 王平[2] 周婷如 王会娟 王雅丽 于浩然 张兴富 YE Chenyang;WANG Ping;ZHOU Tingru;WANG Huijuan;WANG Yali;YU Haoran;ZHANG Xingfu(Lanzhou Jiaotong University,Lanzhou 730070,Gansu,China;Key Laboratory of Loess Earthquake Engineering,CEA,Lanzhou 730000,Gansu,China)

机构地区：[1]兰州交通大学,甘肃兰州730070 [2]中国地震局黄土地震工程重点实验室,甘肃兰州730000

出　　处：《地震工程学报》2025年第2期415-425,467,共12页China Earthquake Engineering Journal

基　　金：地震科技星火计划攻关项目(XH23041C)。

摘　　要：为研究黄土场地地震动放大效应对基础设施的影响,以某简支梁桥为研究对象,基于有限元理论,建立考虑El-Centro波水平耦合作用的桩-土-桥梁模型,并分析其加速度响应、频谱特性以及位移变化,以阐明黄土场地桩-土相互作用特性。研究结果表明:随着地震动峰值加速度(PGA)的增大,桩-土相对位移和桩基峰值加速度均呈明显的增趋势;PGA放大系数随着高程的增加呈正比例增大,结构的卓越频率随着高程的增加逐渐向低频方向移动;傅里叶幅值随着高程的增加逐渐增大;相对于远场土体,桩周土0~20 m范围内峰值加速度最大增加了30.87%。随着桩基长度的增加,桩-土间的相对位移以及桩基加速度响应都明显增大;桩基直径的增大能有效减小桩-土相对位移以及结构的加速度响应。The amplification effect of ground motion on infrastructure found in loess sites was investigated in this study.Taking a simply supported beam bridge as the research object,a pile-soil-bridge model considering the horizontal coupling effect of the El-Centro wave was established based on finite element theory.The analysis focused on acceleration response,spectral characteristics,and displacement response,clarifying the pile-soil interaction characteristics in loess areas.The results reveal that the relative pile-soil displacement and the peak acceleration of pile foundation show an apparent increasing trend with the increase in peak ground accelerations(PGA).Furthermore,as the elevation rises,the PGA amplification factor and Fourier amplitude increase gradually,while the predominant frequency of structure gradually shifts to the low-frequency direction.Compared with the far-field soil,the peak acceleration of loess soil around the pile in the range of 0-20 m increases by 30.87%.With the increase in pile length,the relative pile-soil displacement and the acceleration response of the pile foundation also show an obvious increase.Furthermore,the increase in pile diameter can effectively reduce the relative displacement of pile and soil and a structure's acceleration response.

关 键 词：黄土场地 桩-土相互作用 PGA 频谱特性 地震动响应 

分 类 号：TU435[建筑科学—岩土工程]