大跨度混凝土连续梁桥施工监控参数敏感性分析方法

The Research of the Sensibility Analysis of Design Parameters in Long-Span Concrete Continuous Girder Bridge Construction Monitoring

目的研究在大跨度混凝土连续梁桥施工过程中设计参数对桥梁施工监控的影响,得到主要和次要设计参数.方法利用有限元仿真计算,将各设计参数向上调整10%,得到设计参数调整前后的相应的控制目标的改变量,将这些改变量进行对比分析,判断出对于挠度和截面应力敏感性的主要设计参数.结果在分别增加10%的情况下,自重和截面抗弯惯性矩对挠度的影响在10%左右,而预应力的影响在5.3%,混凝土弹性模量的影响在4.6%.对于截面应力,自重影响为10%,预应力影响为6.9%,弹性模量和截面惯矩影响很小.结论对于悬臂现浇混凝土梁桥,自重和截面抗弯惯性矩的变化对挠度影响较大,自重和预应力的变化对截面应力的影响较大.该结论有利于指导下一阶段的施工.

This paper aims at carrying out the research on the effect of construction monitoring under different design parameters during the construction of long-span concrete continuous girder bridge to get the main and secondary design parameters.During the research,finite element simulation was used.First,each design parameter was increased 10% and the changing variable of corresponding control targets before and after adjustment of design parameters could be reached.The errors arised from the adjustment can be acquired and comparatively analyzed.Then the main and secondary design parameters can be determined.Under the condition of increasing 10% of every design parameter,the deadweight and section inertia moment＇s effects towards deflection are about 10% while the prestress＇ effect is 5.3% and the elastic modulus＇s effect is 4.6%.The deadweight＇s effect toward section stress is 10% and the prestress＇ effect is 6.9%.The section inertia moment and elastic modulus＇s effects are negligible.From the analysis,with the bridge in cantilever construction,the deflection is sensitive to the change of deadweight and the section inertia moment,the section stress is sensitive to the change of deadweight and prestress while it is useful and helpful to conduct and direct the construction on next stage.