立交匝道小半径钢混组合连续梁桥受力特性分析

Mechanical performance of small-radius steel and concrete continuous girder bridges with interchange ramps

以立交小半径匝道桥为工程实例,建立有限元模型,对钢箱梁和混凝土桥面板受力分析。针对墩顶负弯矩区域提出双重组合、先铰接后固结和优化施工顺序3项改善措施。结果表明,各个施工阶段钢箱梁应力和混凝土桥面板横向受力均满足规范要求。采用双重组合和先铰接后固结技术可以降低钢箱梁底板压应力约27.7%和9.8%,优化施工顺序措施能使混凝土桥面板在短期荷载组合下保持受压状态。

Taking the interchange small-radius ramp bridge as an engineering example,a finite element model is established to analyze the steel main girder force and concrete deck slab force.For the negative moment region at the top of the pier,three improvement measures are proposed:double combination,articulation followed by consolidation and optimization of construction sequence.The results show that the stresses of steel box girder and transverse force of concrete deck plate at each construction stage meet the specification requirements.The double combination and articulation followed by consolidation techniques can reduce the compressive stress in the bottom plate of the steel box girder by about 27.7%and 9.8%,and the optimized construction sequence measures can keep the concrete deck in compression under short-term load combinations.