新建桥运营状态下对邻近高铁桥基础水平变形的影响分析  

Analysis of influence of horizontal deformation of adjacent high-speed railway bridges under operation status of newly-built bridges

作　　者：方淑君[1] 张利勇 刘神斌 徐新桐 王涛[1] FANG Shujun;ZHANG Liyong;LIU Shenbin;XU Xintong;WANG Tao(School of Civil Engineering,Central South University,Changsha 410075,China;China United Engineering Corporation Limited,Hangzhou 310051,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075 [2]中国联合工程有限公司,浙江杭州310051

出　　处：《铁道科学与工程学报》2021年第9期2234-2243,共10页Journal of Railway Science and Engineering

基　　金：国家自然科学基金资助项目(51978667)。

摘　　要：临近既有高铁桥梁新建与之并行的桥梁,新建大跨度桥桩基础将荷载作用传递至较深的土体中,并引起既有桥桩基础的附加变形。运用ABAQUS有限元法,采用Mohr-Coulomb弹塑性模型,选取新建桥运营状态下的荷载作用,研究对既有桥桩基础横桥向附加水平变形的影响。研究结果表明:新建桥荷载作用会使桩在横桥向产生转动和局部弯曲并产生附加应力;由于承台的约束作用,群桩在桩顶变形较统一,而在桩底有较大差异;在横桥向变形方面,既有桥前排桩对中后排桩有着明显的遮挡效应;适当增加新旧桥中心距可以减小新建桥对既有桥横桥向附加水平变形的影响;增加新桥桩长可以减小新建桥对既有桥横桥向附加水平变形的影响,但应避免出现较大反向变形的情况。利用有限元方法根据具体工程要求,可以对工程选址提供指导意见。Adjacent to the new high-speed railway bridge,the new large-span bridge pile foundation will transfer the load to the deeper soil and cause additional deformation of the existing bridge pile foundation.In this paper,using the ABAQUS finite element method,the Mohr-Coulomb elastoplastic model was used to select the load effect under the operating condition of the new bridge,and the influence of the transverse bridge on the existing bridge pile foundation to the additional horizontal deformation was studied.The results are drawn as follows.The new bridge load will cause the pile to rotate and partially bend in the transverse bridge direction and generate additional stress.Due to the restraining effect of the pile cap,the group piles are more uniform in the pile top deformation,but there is a big difference in the pile bottom.In terms of bridge deformation,there is a significant occlusion effect on the middle and rear row piles of the bridge front row piles.Appropriate increase of the center distance between the new and old bridges can reduce the influence of the new bridge on the additional horizontal deformation of the existing bridge cross bridge.Increase of the pile length of the new bridge can reduce the influence of the new bridge on the additional horizontal deformation of the existing bridge cross bridge,but it should avoid a large reverse deformation of the situation.The finite element method can be used to provide guidance on the site selection of the project according to specific engineering requirements.

关 键 词：桩-土作用 邻近桩基 横桥向附加水平变形 新旧桥中心距 不同桩长 

分 类 号：TU433[建筑科学—岩土工程]