墩高受限时装配式组合连续刚构桥墩梁固结构造及性能研究

Research on Key Structure and Mechanical Property for Pier Height Limited Prefabricated Combination Continuous Rigid Frame Bridge

针对桥墩高度有限的装配式钢桁-混凝土组合连续刚构桥,为尽量减少墩底出现水平力,在分析结构构造特点和各施工阶段受力行为的基础上,提出了适应于矮墩的墩梁固结构造:利用钢牛腿和墩顶预埋钢板传递施工阶段和运营阶段竖向力;利用抗推挡块抵抗运营阶段水平力,并通过预埋于墩顶钢板下的群钉传递此水平力;利用精轧螺纹钢筋作为安全措施抵抗意外情况下出现的边中跨不平衡拉拔力,保证桥梁安全受力。以实体工程为例,通过有限元方法建立全桥分析模型,分析了桥墩从施工到成桥的力学行为,同时对挡块预埋件式墩梁固结构造进行精细化建模分析。结果表明:与传统的墩梁固结方式相比,该构造可明显降低墩底拉应力,优化墩高受限时钢桁-混凝土组合连续钢构桥墩受力性能,可为桁架连续刚构桥提供参考。

As for the pier height limited Prefabricated Steel Truss-Concrete（PSTC） combination continuous rigid frame bridge,to reduce the horizontal force at the pier base,the pier beam consolidation was recommended for the short pier based on the analysis of the structure characteristics and mechanical behavior at different construction stages.The vertical forces during construction and operation were transferred through the steel corbel and the steel plates embedded at the pier top.The horizontal forces were resisted by the resistance block,and these forces were transferred by the group studs nailed beneath the steel plates at the pier top. As security measures against an unexpected condition of side span unbalanced drawing force,f inishing rolling rebars were used to ensure the bridge safety.In this paper,a full bridge model was built using the finite element method.The mechanical behavior of the bridge starting from construction to bridge completion was analyzed.Also,a refined analysis model was established to analyze the pier beam consolidation with resistance block and embedded part.The results show that the application of the pier beam consolidation structure instead of the traditional structure may significantly reduce the tensile stress at the pier base and optimize the mechanical behavior of pier height limited PSTC combination continuous rigid frame bridge.The study of this structure is meaningful for truss continuous rigid-framed bridges.