大跨度曲线UHPC连续刚构箱梁桥的设计研究与实践

Design Research&Practice of Large-Span Curved UHPC Continuous Rigid Frame Box Girder Bridge

以上海市松江区外下洋路油墩港桥为研究对象,研究基于UHPC的大跨度曲线连续刚构桥的总体设计和构造设计;结合体内及体外预应力布置方式,研究节段箱梁及下部桥墩的装配化施工方案。分别建立空间梁单元模型和整梁空间实体单元模型进行计算分析,并对计算结果进行对比分析。分析结果表明空间实体单元模型的应力分布与空间梁单元相比趋于均匀,采用空间梁单元模型的计算结果进行分析验证偏于安全,结构受力完全满足要求。该工程首次提出采用钢结构横隔板代替传统混凝土横隔板,钢结构横隔板构造简单,便于节段箱梁的预制施工。从空间实体单元模型计算结果来看,钢横隔板与UHPC横隔板的作用效果基本一致,满足结构整体受力性能的需求。

taking Youdungang Bridge on Waixiayang Road,Songjiang District,Shanghai as the research object,the overall design and structural design of long-span curved continuous rigid frame bridge based on UHPC are studied;Combined with the internal and external prestressed layout,the assembly construction scheme of segmental box girder and lower pier is studied.The spatial beam element model and the whole beam spatial solid element model are established respectively for calculation and analysis,and the calculation results are compared and analyzed.The analysis results show that the stress distribution of the spatial solid element model tends to be uniform compared with the spatial beam element.The analysis and verification using the calculation results of the spatial beam element model is partial to safety,and the structural stress fully meets the requirements.It is the first time for this project to adopt the steel structure diaphragm to replace the traditional concrete diaphragm.The steel structure diaphragm has simple structure and is convenient for the prefabrication construction of segmental box girder.From the calculation results of spatial entity element model,the effect of steel diaphragm and UHPC diaphragm is basically the same,which meets the requirements of the overall mechanical performance of the structure.