作者：卫星, 古兴宇, 戴李俊, 肖林

作者单位：西南交通大学土木工程学院，四川 成都 610031

关键词：W型槽梁;顶推施工;有限元模型;剪力滞效应;剪力滞系数

摘要：

为分析城市轨道交通W型槽梁在顶推施工过程中的时变剪力滞效应，该文以某轨道交通W型槽梁桥为工程背景，建立Ansys和Midas三维有限元实桥模型，计算得到顶推过程中梁体内力变化情况及关键截面纵桥向正应力分布状态，研究得到W型槽型梁截面剪力滞系数的时变规律。研究表明：底板在顶推施工过程中同位置剪力滞效应可能出现正负性质的改变；中间腹板和两侧腹板处剪力滞效应的正负性质大多相反；底板最大剪力滞系数与截面正弯矩存在一定程度正相关；最大悬臂截面剪力滞系数约在0.79~1.58范围内出现，该类桥型设计时需要考虑施工阶段应力状态。

Time-varying shear lag effect of rail transit W-shaped channel girder in incremental launching construction
WEI Xing, GU Xingyu, DAI Lijun, XIAO Lin
School of Civil Engineering, Southwest Jiaotong University, Chengdu 610031, China
Abstract: To investigate the time-varying shear lag effect of rail transit W-shaped channel girder section in incremental launching construction, taking a W-shaped channel girder bridge as the engineering background, 3D finite element models of ANSYS and Midas were established. The variation of the internal force of beam and the distribution of the longitudinal normal stress of key sections were calculated. The time-varying characteristic of the shear lag coefficient of W-shaped channel girder sections was obtained. The research results indicates that the shear lag effect at the same position of the lower plate may change positively and negatively during incremental construction. The positive and negative properties of the shear lag effect at the intermediate web and the webs on both sides are mostly opposite. The maximum shear lag coefficient of the lower plate is positively correlated with the positive bending moment of the section. The shear lag coefficient of maximum cantilever section approximately appears in the range of 0.79-1.58. The design for this type of bridges needs to consider the stress state during the building phase.
Keywords: W-shaped channel girder;incremental launching construction;finite element model;shear lag effect;shear lag coefficient
2021, 47(6):91-94  收稿日期: 2020-10-15;收到修改稿日期: 2020-11-28
基金项目: 四川省科技创新人才项目（2020JDRC0009）
作者简介: 卫星(1976-),男,山西沁源县人,教授,博士,主要从事桥梁力学行为研究
参考文献
[1] 卫星, 杨世玉. 单箱双室波形钢腹板PC箱梁剪力滞效应分析[J]. 铁道工程学报, 2017, 34 (3): 29-33
[2] 邹建波, 赵人达. 支承形式对波形钢腹板预应力混凝土曲线箱梁剪力滞效应的影响[J]. 铁道建筑, 2018, 58 (8): 7-9
[3] 董艳彪, 方智淳, 马瑞峰, 等. 梯形荷载作用下箱梁剪力滞效应分析[J]. 兰州工业学院学报, 2018, 25 (4): 1-6
[4] 卢海林, 蔡恒, 汤正. 移动荷载作用下薄壁曲线箱梁剪力滞效应分析[J]. 铁道建筑, 2016(9): 14-18
[5] BOULES P F, MEHANNY S S F, BAKHOUM M M. Shear lag effects on wide U-section pre-stressed concrete light rail bridges[J]. Structural Engineering and Mechanics, 2018, 68 (1): 67-80
[6] HENRIQUES D, GONÇALVES R, CAMOTIM D. A physically non-linear GBT-based finite element for steel and steel-concrete beams including shear lag effects[J]. Thin-Walled Structures, 2015, 90: 202-215
[7] 潘旦光, 付相球, 韦杉杉, 等. 变高度悬臂箱梁剪力滞效应的半解析解[J]. 工程力学, 2018, 35(9): 207-213
[8] 张玉元, 张元海, 张慧. 考虑剪力滞效应影响的箱形梁弯曲剪应力分析[J]. 兰州交通大学学报, 2020(1): 27-33
[9] 马驰, 刘世忠, 陈权, 等. 波形钢腹板-钢底板-混凝土顶板组合箱梁的有效分布宽度研究[J]. 铁道科学与工程学报, 2020, v. 17; No. 122(5): 124-131
[10] AL-SHERRAWI M H, MOHAMMED S N. Shear lag in composite steel concrete beams[C]//2018 1st International Scientific Conference of Engineering Sciences, 2018.
[11] 赵玉如, 苑俊杰, 秦长坤. 碳纤维复合材料薄壁箱梁剪力滞后效应数值分析[J]. 河南工程学院学报(自然科学版), 2018, 30 (3): 38-39, 58
[12] 潘湘文. 基于能量变分法的连续槽型梁桥剪力滞效应分析[J]. 结构工程师, 2012, 28(1): 45-49