后续束控制大跨径刚构—连续梁桥长期性能研究

Research on Long-term Performance of Large-span Rigid Frame Continuous Girder Bridge by Follow-up Beam Control

由于混凝土收缩徐变、预应力钢筋松弛等因素作用,大跨径预应力桥梁主梁的长期性能(应力、挠度)出现一系列问题,如:跨中出现裂缝、主梁下挠不断增大等。采用理论分析和数值模拟相结合的研究手段,结合工程实例,根据桥梁的具体情况建立模型,对张拉不同位置(顶板束、腹板束及底板合拢束)的钢束对提高主梁的受力和减小主梁挠度的效率进行分析研究,得出最佳的预留孔道的位置。

Due to the role of factors like concrete shrinkage and creep, prestressed reinforcement relaxation and so on, the long - term performance （ stress, deflection） of main girder of large - span prestressed bridge has a series of problems, such as crack in midspan, continuous increase of down deflection of main girder and so on. The research means of combining theoretical analysis and numerical simulation is adopted. In combination with project case, the analytical research is made on the steel beam at different positions of tension （ top plate beam, web beam and closing beam of bottom plate） for the improvement of stress of main girder and efficiency of reducing the deflection of main girder by building the model according to the specific condition of the bridge, so as to obtain the best position of reserved pore passage.