大跨度预应力混凝土连续梁桥关键设计参数敏感性分析

SENSITIVITY ANALYSIS OF KEY DESIGN PARAMETERS OF LONG SPAN PRESTRESSED CONCRETE CONTINUOUS GIRDER BRIDGE

以江家大桥作为研究对象,建立模型进行有限元分析,对比分析主梁自重、预应力钢束及管道摩擦系数变化对主梁内力、线形以及主要控制截面上下缘应力的影响,进而分析出主要敏感性参数。并以主要敏感性参数变化,分析其对主梁主要控制截面上下缘应力的影响。分析结果表明,主梁自重为主要敏感性参数,主梁自重变化对主梁内力、线形、应力影响较大,在施工过程中应对影响主梁自重变化的因素应进行严格控制。

Taking Jiangjia bridge as the research object,the model is established by using the bridge doctor V3.6 software for finite element analysis,and the effects of the changes of the self weight of the main beam and the friction coefficient between the prestressed tendon and the pipeline on the internal force,the alignment,and the upper and lower edge stress of the main control section are compared and analyzed,so as to separate the main sensitive parameters.Based on the change of main sensitivity parameters,the influence on the stress of the upper and lower edges of the main control section of the main beam is analyzed.The results show that the self-weight of the main beam is the main sensitive parameter,and the change of the self-weight of the main beam has a great impact on the internal force,alignment,and stress of the main beam.The factors affecting the change of the self-weight of the main beam should be strictly controlled in the construction process.