先简支后连续T梁桥全过程力学行为及极限承载力分析
Study on full loading process performance of simplysupported continuous T-beam bridge

为研究先简支后连续T梁桥从施工至极限破坏的全过程受力性能，以河南省省道S318线西张村大桥为工程背景，运用有限元软件midas/FEA建立同时考虑几何非线性和材料非线性影响的全桥三维实体模型，分别在6种工况下进行了仿真分析研究。研究结果表明：桥梁达到极限承载力时，偏载工况下的活荷载系数小于相应对称荷载工况下的活荷载系数；偏载工况下边梁相应的支座截面底部混凝土先被压碎，对称荷载作用下，受荷位置主梁相应关键截面顶板的混凝土先被压碎；预制主梁上缘的混凝土先于湿接缝处的混凝土达到极限应力状态，二者受力不同步。
The paper studied the stress performance of simply supported continuous T-beam bridge from construction stage to the ultimate failure. By considering the material and geometric nonlinear conditions, the finite element software Midas/FEA was used to simulate the three-dimensional solid model of a full-bridge under the six kinds of conditions in the engineering background of Xizhangcun Bridge in Henan Province Highway S318. The results showed that: The live load factor in unbalance loading working condition was less than that of balanced when the bridge reach the ultimate bearing capacity; The concrete in the bottom of support cross-section of the spandrel beam was crushed firstly in unbalance loading working condition; In the condition of balance loading working the concrete in the top of the key sections of girder at the load position was crushed firstly; The concrete at the top of the girder precast reached the critical stress earlier than in the wet-joint and their force were asynchronous