基于动力特性的大跨径连续刚构桥的敏感性分析

Sensitivity analysis of long span continuous rigid frame bridge based on dynamic characteristics

桥梁长期置于外界自然环境中,不可避免的会受到众多因素的影响,桥梁的各部分构件的性能均会随时间发生不同程度的变化,这不仅会对桥梁的静力特性产生很大的影响,对桥梁结构的动力特性同样有很大的影响,但是对动力特性的影响关注较少。为了研究哪些参数对桥梁的动力特性影响最大,本文以某大跨径连续刚构桥为依托工程,利用ANSYS有限元软件建立了某大跨连续刚构桥梁全桥有限元模型,研究了弹性模量、预应力钢筋损失、混凝土容重等几种主要因素对大跨径连续刚构桥梁的动力特性的影响,从而得到该类桥型的模态频率敏感性最大的因素,为以后对连续刚构桥梁的维修加固及动力特性研究提供依据。

Bridges are exposed in the external natural environment, will be affected by many factors. The per- formance of each component of the bridge will have different variation over time. It will not only affect the static characteristics of the bridge, but also has a great influence on the dynamic characteristics of the bridge structure. However, there is little study about the dynamic characteristics. In order to investigate the parameters influence dy- namic characteristics of the bridge based on a large span continuous rigid frame bridge project, this paper a finite element model using ANSYS finite element software to study the influence of dynamic characteristics of bridge with the elastic modulus, prestress steel loss, concrete bulk density. Therefore, the most important factor influence mod- el frequency sensitivity of bridge was found. It could be reference for repair, reinforcement and dynamic character- istics study of continuous rigid frame bridge.