考虑碎石桩加固的液化场地桥梁地震风险分析  

Seismic Risk Assessment of an Liquefaction Ground Bridge System Using Stone Column for Reinforcement

作　　者：古泉[1] 俞至权 邱志坚[1] GU Quan;YU Zhiquan;QIU Zhijian(School of Architecture and Civil Engineering,Xiamen University,Xiamen 361005,China)

机构地区：[1]厦门大学建筑与土木工程学院,福建厦门361005

出　　处：《湖南大学学报（自然科学版）》2022年第7期178-185,共8页Journal of Hunan University:Natural Sciences

基　　金：国家自然科学基金资助项目(51978591,51578473);中央高校基本科研业务费专项资金资助项目(22070103963,20720220070)。

摘　　要：以一座典型的四跨钢筋混凝土连续桥梁为例,建立三个液化场地桩-土-桥梁体系平面应变有限元模型,考虑饱和土体中孔隙水与土颗粒的动力耦合效应,探究碎石桩作为桥梁工程抗液化加固措施的效果.通过构建液化场地桥梁结构的易损性曲线和地震危险曲线,在概率理论框架下诠释碎石桩加固措施对桩基桥梁地震风险的影响,并对有无碎石桩加固措施的计算结果进行对比分析.结果表明:碎石桩抗液化效果显著,可以有效减少土体的超孔隙水压,进而大幅降低液化场地桥梁的整体侧向变形、破损概率和地震风险.A typical four-span reinforced concrete continuous bridge is employed as examples in this paper,and a plane strain Finite Element(FE)analysis model is developed for three liquefaction pile-ground-bridge systems.Considering the dynamic coupling effect between the pore water and soil particle in the saturated soil,the effect of stone column as a liquefaction countermeasure on excess pore pressure buildup and overall bridge-ground system seismic response are systematically investigated.In addition,the influences of stone columns on the bridge’s seismic fragility and earthquake hazard curves are explored through constructon of the liquefaction ground–bridge structures.Based on the probability theory,the effect of reinforcement measure using the stone column on the seismic risk of the pile-ground-bridge system is established,and the results with/without stone column scenarios are compared.The results show that the stone column has a significant effect on the sand liquefaction.The use of stone columns can significantly reduce the excess pore pressure of soil,thus lowering the bridge-ground system’s overall deformation,seismic vulnerability,and earthquake risk.

关 键 词：砂土液化 碎石桩加固 桩-土-桥梁结构 易损性 地震风险性 

分 类 号：TU473.1[建筑科学—结构工程]