节段法施工连续箱梁桥的精细化计算分析  

A Fine Calculation Analysis of Segmental Method Construction for Continuous Box Girder Bridges

作　　者：李俊 卢雄强 赵小龙 李新平[3] LI Jun;LU Xiongqiang;ZHAO Xiaolong;LI Xinping(Guangdong Dadao Testing Technology Co Ltd,Zhongshan 528400,China;Guangzhou Yuedong Country Garden Investment Co Ltd,Guangzhou 510000,China;School of Civil Engineering and Transportation,South China University of Technology,Guangzhou 510641,China)

机构地区：[1]广东大道检测技术有限公司,广东中山528400 [2]广州粤东碧桂园投资有限公司,广东广州510000 [3]华南理工大学土木与交通学院,广东广州510641

出　　处：《五邑大学学报（自然科学版）》2024年第4期42-49,共8页Journal of Wuyi University(Natural Science Edition)

摘　　要：建立精细化实体有限元模型计算分析能较准确地模拟桥梁结构的实际应力状态.本文采用有限元软件Midas/FEA建立精细化实体有限元模型对节段法施工的连续箱梁桥应力进行分析.通过对箱梁桥施工过程进行模拟计算,截取其中3个箱梁节段的计算应力状态进行分析发现:在预应力束锚固的局部应力的影响下,在距锚固端一定距离的位置的箱梁节段上存在一个应力峰值,且沿腹板高度的应力分布不为直线.进一步将全桥精细化有限元模型计算结果与Midas/civil杆系有限元模型计算的结果进行对比,两个模型计算的箱梁节段的最大应力比值随施工节段的增加而逐渐减小,成桥状态时最大纵向正应力比值在1.28~1.34,大于箱梁剪力滞系数.这表明采用Midas/civil杆系有限元模型进行节段法施工的箱梁桥设计时,不仅要考虑箱梁剪力滞效应,也要考虑锚下局部应力的影响.Establishing a refined solid finite element model for calculation and analysis can accurately simulate the actual stress state of bridge structures.This article adopts the finite element software Midas/FEA to establish a refined solid finite element model for stress analysis of continuous box girder bridges constructed using the segmental method.By simulating the construction process of a box girder bridge and analyzing the calculated stress states of three box girder segments,it was found that under the influence of local stress of prestressed tendon anchoring,there is a stress peak on the box girder segment at a certain distance from the anchoring end,and the stress distribution along the web height is not straight.Further comparing the calculation results of the refined finite element model of the entire bridge with those of the Midas/Civil member system finite element model,the maximum stress ratio of the box girder segment obtained by the two models gradually decreases with the increase of the construction segment.The maximum longitudinal normal stress ratio in the completed bridge state is between 1.28 and 1.34,which is greater than the shear lag coefficient of the box girder.This indicates that when using the Midas/Civil member system finite element model for segmental construction of box girder bridges,not only the shear lag effect of the box girder but also the influence of local stress under the anchor should be considered.

关 键 词：精细化有限元 大跨度预应力混凝土 箱梁桥 节段法 应力 

分 类 号：U442.5[建筑科学—桥梁与隧道工程]