高铁预应力混凝土连续梁顶升更换支座模拟分析

高速铁路桥梁建设发展迅速,随之而产生的桥梁支座更换工作也越来越多。桥梁支座更换最常用的方法是梁体顶升法,施工时必须对梁体结构的变形及应力状态进行控制。主要阐述了桥梁支座更换方案及梁体顶升过程的模拟分析,给出了三跨连续梁不同墩顶竖向位移对梁体线形及内力的影响,从而根据规范要求,确定顶升的位移控制限值及对应梁体混凝土应力限值,并作为施工的依据,施工监测数据与结构分析数据取得一致,保证了支座更换的顺利完成。

The Simulation Analysis of the Lifting Operation of the Continuous Pre-Stressed Concrete Beam for High-Spccd Railways During the Replacement of the Bearing

The replacement of the bearing of bridges has to be performed more and more frequently with the rapid development of the construction of high-speed railway bridges in our country. The most commonly used method for the replacement of the bearing of bridges is the beam-lifting method. During the replacement, the deformation and the stress condition of the structure of the beam have to be controlled. The scheme for the replacement of bridge bearing and the simulation analysis of the beam- lifting process are dealt with in the paper, with the effects of the longitudinal displacement of the three-span continuous beam at different pier tops on the linearity and internal forces of the beam obtained. According to the requirements of the technical spec- ifications, the maximum allowable lifting displacement and the corresponding stress limits of the beam concrete are determined, which will be used as the grounds of construction. The monitored values at the site are found to be in agreement with the values of the structural analyses, which ensure the smooth completion of the replacement of the bearing of the bridge.