城市桥梁改建过程中对既有旧桥利用的研究

Research on the Utilization of Existing Bridges in the Process of Urban Bridge Reconstruction Based on Bearing Capacity Factors

肇庆枫湾桥由15.5m简支T梁改建为3跨连续下承式钢结构系杆拱桥,新桥施工时利用旧桥作为临时施工便道,采用1台350t、1台400t汽车式起重机站在旧桥上方吊装构件。以旧桥T梁承载力为控制变量,通过路基箱使2片T梁承受1台汽车式起重机支腿荷载,整个吊装过程平稳,旧桥主梁变形可控,无明显裂缝。

Fengwan bridge is rebuilt from 15.5 m simply supported T beam to three span continuous through steel structure tied arch bridge,and old bridge was used as construction road when new bridge was constructed.the components of the new bridge was lifted by one 350 t and one 400 t truck cranes on the old bridge.Taking the bearing capacity of the old bridge T beam as the control variable,with wo beams bearing the weight of one truck leg by subgrade box,the whole process of lifting was safety and steady,the deformation of the old bridge was controlled and no apparent fracture.It can be an example for the same bridge construction.