既有箱梁移至邻近新建高铁线条件下帮宽桥墩受力分析  

Stress Analysis of Widening Bridge Pier under Moving Existing Box Girder to Adjacent New High Speed Railway Line

作　　者：张晓华 李逢林 李伟超 李战胜 卢文良[2] ZHANG Xiaohua;LI Fenglin;LI Weichao;LI Zhansheng;LU Wenliang(China Railway Design Corporation,Tianjin 300142,China;School of Civil Engineering,Beijing Jiaotong University,Beijing 100044,China)

机构地区：[1]中国铁路设计集团有限公司,天津300142 [2]北京交通大学土木建筑工程学院,北京100044

出　　处：《工程质量》2024年第9期39-43,共5页Construction Quality

摘　　要：论文以既有箱梁移至邻近新建高铁线条件下的帮宽桥墩为研究对象,介绍了墩身帮宽方法、施工工艺及界面植筋情况,建立了帮宽桥墩有限元模型,对比研究了墩身帮宽前后的受力特性。结果表明:墩身帮宽前后的最大主拉应力分别为 0.17 MPa、1.06 MPa,均小于 C35 混凝土的轴心抗拉强度标准值 2.20 MPa,墩身受力性能较好;墩高约 2.2~7.7 m 范围内,接缝面法向正应力由帮宽前的受压转变为帮宽后的受拉,但数值较小;墩身帮宽后接缝面的切向剪应力绝对值较墩身帮宽前的小,接缝面受力状态较为理想;墩身处于弹性阶段,工作性能良好。Taking widening pier under moving existing box girder to adjacent new high speed railway line as the research object,this paper introduces the widening method,construction technology and implant reinforcing bar,establishes the finite element model of widening pier,and compares the stress characteristics of pier body before and after widening.The results show that the maximum principal tensile stress before and after the widening of pier is 0.17 MPa and 1.06 MPa,which are both less than the standard value of axial tensile strength of C35 concrete 2.20 MPa,and the pier has good stress performance.Within the range of pier height of about 2.2~7.7m,the normal stress of the joint surface changes from compression before widening to tension after widening,but the value is small.The absolute value of vertical shear stress on the joint surface after widening is smaller than that before widening,and the force state of the joint surface is ideal.The pier is in the elastic phase and has good working performance.

关 键 词：高速铁路 箱梁 桥墩 帮宽 新老混凝土 植筋 数值模拟 

分 类 号：U442[建筑科学—桥梁与隧道工程]