旧澜石大桥拆除安全分析研究

Safety Analysis of Old Lanshi Bridge Dismantled

旧澜石大桥原设计航道等级为Ⅳ级,桥下通航净高≤8m,由于航道升级为Ⅱ级,净高要求升级为10m,已满足不了航道升级要求,经全方位评估,对其进行拆除。本文针对旧澜石大桥拆除过程采用有限元分析软件进行安全分析,包括拱上建筑拆除及主拱爆破安全,根据分析结果指导拆除施工顺序及主拱爆破孔的设置问题,同时对主拱圈爆破塌落导致澜石二桥、三桥桥位处地面振动及波浪力的影响进行了分析。

Old Lanshi Bridge original design grade class Ⅳ waterway,the clearance under the bridge is less than 8 meters. Due to the upgrading of the waterway,the clearance under the bridge should be more than 10 meters. Old Lanshi Bridge which should be dismantling could not meet the requirements. In this paper,the safety analysis of the process of dismantling the old bridge Lanshi using finite element analysis will be listed,including spandrel construction demolition and blasting safety of the main arch. The analysis results will guide the demolition construction sequence and the setting of the blasting hole. The Influence of the ground vibration and wave force which are caused by the collapse of the main arch are analyzed.