高墩大跨连续刚构桥施工全过程稳定性分析  

Stability Analysis of Whole Construction Process of High Pier and Long Span Continuous Rigid Framed Bridge

作　　者：王博妮 马海涛 张明明 WANG Boni;MA Haitao;ZHANG Mingming(Zhengzhou Design Institute of China Railway Engineering Design and Consulting Group Co.Ltd.,Zhengzhou 450001,China)

机构地区：[1]中铁工程设计咨询集团有限公司郑州设计院,郑州450001

出　　处：《铁道建筑》2024年第6期96-101,共6页Railway Engineering

基　　金：中铁工程设计咨询集团有限公司科研项目(研2020-48)。

摘　　要：本文以三门峡国道209上跨陇海铁路立交桥为研究对象,采用MIDAS/Civil建立裸墩、最大双悬臂和成桥合龙3种状态下的有限元模型,对主墩进行线性屈曲分析和几何非线性屈曲分析,计算出稳定性系数,探讨不同荷载工况下稳定性的影响因素。通过调整桥墩主要设计参数,对主墩进行稳定性影响参数的敏感性分析。结果表明:全桥施工及成桥状态下,墩顶施工荷载、挂篮荷载、温度效应和车道荷载对主墩的稳定性影响较大;在稳定性影响参数敏感性分析中,随壁厚和混凝土强度等级的提高,稳定性系数逐渐增大;墩高的增加会使稳定性系数逐渐降低,但降低速率会逐渐减缓;系梁数量和位置均会对稳定性产生显著影响;随主墩高差的减小,稳定性系数逐渐降低,桥梁结构荷载重分配,墩顶主梁弯矩逐渐降低。Taking the overpass of Longhai Railway on Sanmenxia National Highway 209 as the research object,finite element models were established by using MIDAS/Civil for three states of bare pier,maximum double cantilever,and bridge closure.Linear buckling analysis and geometric nonlinear buckling analysis were performed on the main pier to calculate the stability coefficient and explore the influencing factors of stability under different load conditions.By adjusting the main design parameters of the bridge pier,sensitivity analysis of the stability impact parameters of the main pier was conducted.The results show that the stability of the main pier is significantly affected by the construction load on the pier top,the hanging basket load,the temperature effect,and the lane load during the whole bridge construction and completion state.In the sensitivity analysis of stability influencing parameters,the stability coefficient gradually increases with the increase of wall thickness and concrete strength grade.On the other hand,the stability coefficient gradually decreases with the increase of pier height,but the rate of reduction slows down.Additionally,the number and location of tie beams significantly impact the stability of the structure.As the height difference between the main piers decreases,the stability coefficient also decreases,causing a redistribution of the bridge structure load and a gradual decrease in the bending moment of the main girder at the top of the pier.

关 键 词：铁路桥梁 稳定性 有限元模拟 大跨连续刚构桥 高墩 

分 类 号：U448.23[建筑科学—桥梁与隧道工程]