摘要
以某大跨度连续箱梁桥梁体顶板加劲腋纵向开裂为背景,建立考虑悬臂施工和成桥运营阶段的大桥三维实体有限元模型,分析了横向预应力张拉、挂篮前移、施工不平衡堆载、重车偏载、梯度温度等不同荷载工况对箱室顶板加腋处横向应力分布的影响。结果表明,施工/运营阶段最大组合应力接近混凝土抗拉强度标准值,对大悬臂箱梁,横向预应力张拉是引起梁体纵向裂缝的主要原因。
To discuss the reasons for longitudinal cracking, an existing long-span PC continuous girder bridge is taken as the research background. Considering processes of cantilever construction and operation, a 3D solid FE model is built. Influences of lateral prestressing, hanging basket, unbalance site load, unbalance heavy vehicle and gradient temperature on haunches of top deck are discussed. The result shows that the maximum combined stress in construction stage or operation stage is close to the tensile strength of concrete, and lateral prestressing is the main reason for longitudinal cracks in broad flange box girder.
出处
《公路》
北大核心
2017年第4期75-78,共4页
Highway
关键词
箱梁桥
开裂
大悬臂箱梁
横向应力
分析
box girder bridge
cracking
broad flange
transversal stress
analysis
