基于成桥状态下钢-混拱梁组合体系桥梁的力学参数敏感性分析研究

Analysis of the Mechanics Parameter Sensitivity of the Bridge Based on the Steel-concrete Arch Composite System in the Completed State

本文主要研究钢-混拱梁组合体系桥梁在不同使用工况下的受力特性,确保桥梁结构在不利荷载作用下能够满足设计要求和具有良好的成桥状态。以西北某市桥梁为依托工程,采用Midas/Civil空间有限元分析软件,选取铺装层的超欠方量、温度的整体升降作用、混凝土的收缩徐变作用为参数,进行该体系桥梁的力学参数敏感性分析。研究结果表明:整体升降温对主梁的受力及变形的影响最为显著,收缩徐变次之,铺装层超欠方最小;温度等的作用会在该高次超静定结构中产生很大的次内力;混凝土的收缩徐变作用呈现出先发展很快后逐渐趋于稳定的规律。并通过修正参数对桥梁的施工进行控制,得到成桥阶段主梁及桥面板主梁及桥面板受力状况良好。此研究结构体系桥梁的设计具有一定的指导意义。

The article studies steel - mixed composite arch bridge system＇ s mechanical characteristics under different operating conditions, to ensure that the bridge structure satisfies the design requirements and has a good state under unfavorable load. Based on a city bridge in northwest China, with space finite element analysis software of Midas/Civil, we select temperature effect, concrete shrinkage and creep function as a parameter, and conduct an mechanical parameters sensitivity analysis of this bridge. The resuhs prove that the overall temperature has the most significant impact on the stress and deformation of girders, shrinkage and creep take the second place, and the influence of the pavement layer is minimal. The temperature and others may come about a great second inner force in the structure. The shrinkage and creep effect of concrete presents quickly before they are gradually stabilized. Therefore, the bridge construction is controlled by the modified parameters, and the linear condition of the main girder and deck slab in the bridge stage is good, the relative error is less than 5% , the main girder and the deck slab are in good condition, which has certain guiding significance to the design of the system bridge.