大跨宽幅转体桥梁现浇支架设计及安全评估

Research on design and safety evaluation of cast-in-situ supports for large-span and wide swivel bridges

大临结构施工属于桥梁现浇施工中的高风险环节,临时施工支架的合理化设计与精确化计算至关重要。依托宁梁高速上跨京九铁路立交桥工程,利用有限元软件对大跨宽幅转体桥梁现浇支架体系的关键构件进行建模分析,并对支架不同构件的安全储备进行对比。通过计算分析表明:现浇支架关键构件的应力和变形均满足规范要求,各个构件安全系数差异较大,对安全储备较少的部位应采取合理的局部加强措施和重点监控。

The construction of the Dalin structure is a high-risk part of the cast-in-place bridge construction,and the rational design and accurate calculation of the temporary construction support are very important.Relying on the Ning-Liang High-speed overpass project of the Beijing-Kowloon Railway,the finite element software is used to model and analyze the key components of the cast-in-place support system of the large-span wide swivel bridge,and to compare the safety reserves of different components of the support.The calculation and analysis show that the stress and deformation of the key components of the cast-in-place support meet the requirements of the specification,and the safety factors of each component are quite different.Reasonable local strengthening measures and key monitoring should be adopted for the parts with less safety reserves.