北江大桥主桥反顶推拆除施工技术

Technology of the Reverse Incremental Launching Method for Demolition of the Main Bridge of Beijiang Bridge

针对北江大桥拆除作业空间狭小、拆除施工存在较大安全风险、无任何经验可借鉴等特点,结合现场实际情况,最终采用安装钢导梁实施反顶推拆除施工方案。实践表明:反顶推拆除施工方案简单,安全操作性强,节省大量施工成本,同时不影响已建成通车侧桥的通畅运行。现场监控实测主梁段应力值和应变值与模拟计算值误差较小,反顶推拆除施工方案在北江大桥主桥拆除中成功实施,为今后旧桥拆除施工积累宝贵经验。

Because of the difficult demolition work of Beijiang Bridge, including small working space, high secu- rity risk and demolition construction without any experience, the reverse incremental launching demolition con- struction scheme with installation of steel girder has been adopted under the actual situation. The results show that： reverse incremental launching demolition construction scheme is simple and safe, and can save a large a- mount of construction cost. Most importantly, it can prevent highway traffic from being obstructed. And there is little error in the stains and stresses on the main bridge between on-site monitoring measurement and stimulation calculation. The reverse incremental launching demolition construction scheme has been successfully implemen- ted in the demolition of the main bridge of Beijiang Bridge, accumulating a wealth of experience for the demoli- tion of old bridges in the future.