纵挑横抬梁法加固线路在顶进式框架桥工程中的应用

Application of the Longitudinally-Suspended and Horizontally-Raised-Beam Track-Reinforcing Construction Method to the Projects of Frame Bridges

在框架桥顶进施工时,采用D型便梁加固线路时受立交桥跨度和斜交角度的限制,适应性较差。H型钢组拼纵挑横抬梁法加固是指通过采用型钢组拼的纵梁沿线路方向将既有线路挑起、沿框架桥方向组拼的横梁承受纵梁传递的线路荷载,实现结构受力由纵向向横向的转变。结合工程实例介绍了宽翼缘H型钢组拼纵挑横抬梁法加固线路方式的结构构造特点和近似检算方法。实践证明该方法安全可行,具有推广价值。

In the jacking construction of frame bridges, the use of D-type beams for strengthening the track is often limited by the spanning length of the flyover and oblique angles, as a result Of which the construction method is very poor in adaptability. The method of using H-type steel-assembled longitudinally-suspended and horizontally-raised beams for the reinforcement of the track means using formed-steel-assembled longitudinal beams to suspend the existing track along the line,while the assembled lateral beams are used to raise the longitudinal-beam-passed track loads along the direction of the frame bridge, thus converting the forces acting on the structure from tiae longitudinal direction to the horizontal direction. With practical engineering examples used to illustrate the principles, the structural characteristics of the wide-flange H-type steel-assembled beams used to longitu- dinally suspend and horizontally raise the track loads and the approximate checking methods are introduced in the paper. Construction practice proves that the method is feasible, safe, and worth popularizing.