运营状态下新建桥对邻近高铁桥梁沉降的分析  

Influence of new bridge loading on additional foundation settlement of existing bridge

作　　者：方淑君[1] 徐新桐 王涛[1] 张利勇 刘神斌 FANG Shujun;XU Xintong;WANG Tao;ZHANG Liyong;LIU Shenbin(School of Civil Engineering,Central South University,Changsha 410075,China;China United Engineering Co.,Ltd.,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》2022年第5期1187-1195,共9页Journal of Railway Science and Engineering

基　　金：国家自然科学基金资助项目(51978667)。

摘　　要：随着新建桥梁结构的不断增多,关于新建桥梁对于既存桥梁结构影响的研究亟待进行与发展。以某中间层处于软土层的地区某刚构桥为分析对象,以工程中常用的三维建模软件ABAQUS为分析建模工具,对目标附近新建并与之邻近的桥梁进行分析,得到既有桥梁基础在新建桥梁荷载影响下产生的在桩顶、桩底及整个桩体直线上的附加沉降等相关数值数据。在分析讨论过程中通过使用控制变量法,在不改变地质工程等条件的同时分别改变新旧桩中心矩等参数,得到相应条件下的沉降值等数据并进行分析,从而归纳总结出对应变量与沉降之间的关系。研究结果表明:1)新桥荷载间接作用于既有桥基础上,受到间接荷载作用的既有桥桩基桩顶附加沉降量的大小由桩底土的附加沉降决定;2)既有群桩基础中与新建基础距离最近的桩产生的附加沉降量最大,不同基础间距产生不同的附加沉降;3)桩基础的桩顶附加沉降量在桩顶荷载、桩基和土层等因素确定的情况下,只与新旧基础间距有关,并给出关系式;4)既有桩土受到新加荷载影响而产生的附加沉降量与两者间的距离呈现负相关的关系,当距离大于一定范围后,既有基础的附加沉降量趋于一个稳定值,由此可对相同条件下的工程提供指导意见。With the increasing number of new bridge structures,the research on the impact of new bridges on existing bridge structures needs to be carried out and developed.Therefore,a rigid frame bridge in a region with soft soil layer in the middle layer was taken as the engineering object of analysis,and ABAQUS,a threedimensional modeling software commonly used in engineering,was used as the analysis and modeling tool to analyze the newly built and adjacent bridge near the target.The additional settlement on pile top,pile bottom and the whole pile line of the existing bridge foundation under the influence of the new bridge load was obtained.In the process of analysis and discussion,by using the control variable method,the central moment and other parameters of the old and new piles were changed respectively without changing geological engineering conditions,and the settlement value and other data under the corresponding conditions were analyzed.Finally,the relationship between the corresponding variables and settlement was summarized.The main conclusions are as follows.1)The new bridge load acts indirectly on the existing bridge foundation,and the additional settlement of the pile top of the existing bridge pile foundation under the indirect load is determined by the additional settlement of the pile subsoil.2)In the existing pile group foundation,the pile closest to the newly built foundation produces the largest additional settlement,and different foundation spacing produces different additional settlement.3)The additional settlement of pile top of pile foundation is only related to the distance between old and new foundation when pile top load,pile foundation,soil layer and other factors are determined,and the relational formula is given.4)There is a negative correlation between the additional settlement of the existing pile and soil affected by the new load and the distance between the two.When the distance is greater than a certain range,the additional settlement of the existing foundation tends to a stable value,wh

关 键 词：桥梁基础 地基附加沉降 邻近桩基 软土地层 MOHR-COULOMB模型 

分 类 号：TU47[建筑科学—结构工程]