钢筋混凝土梁柱轴向预埋孔长袋水耦合精确装药爆破拆除技术

Explosive Demolition of Reinforced Concrete Beam and Column by Water Coupling Accurate Charging with Pre-buried Axial Holes and Long Bag

钢筋混凝土梁柱的拆除是建筑物拆除的关键技术,为了取得良好爆破效果,减少对城市周边环境的影响和破坏,需要精确装药和严格控制爆破有害效应。为此发明了在梁柱中布置两端向上弯起、中间平直的轴向预埋孔、水耦合装药方法、牵引绳线拖拽内置若干格室的装药长袋实现精确间隔和不耦合装药的技术方案。该方案首次在武汉某基坑支撑梁拆除中使用,采用的主要技术参数为:预埋中间平直段长度不大于4m、两端弯起45°的50 mm PVC管作为炮孔;孔内注满水;使用涤纶制作的内径40 mm装药长袋(装药间隔30 cm、单点药量27~60 g)并在袋内布置通长导爆索。配合采用沙袋水袋压渣降尘、切割箍筋、覆盖柔性防护网防护等措施,成功实现了低成本的精确绿色爆破拆除。

Demolition of reinforced concrete beam and column is key to demolition of building structures. In order to achieve good blasting effect and to reduce the influence and damage to the surrounding cnvironment of the city,it is necessary to conduet accurate charge and strictly eontrolling the harmful impact of blasting. For this purpose, we have invented the technology featured as pre-burying pipes as blasting holes with two ends bent up to the top and middle section straight, the water coupling charge method and dragging the long charging bag with several lattice chambers by hauling rope, with to achieve accurate interval and decoupling charge. When this technology was applied for the first time in a foundation pit support beam demolition blasting project in Wuhan,the main technical parameters are given as,the pre-buried PVC pipes with a diameter of 50 mm with less than 4 m intermediate section straight and two ends bent up 45° as demolition boles,the holes filled with water,long charge bag made of polyester with a internal diameter of 40 mm （ the charge interval of 30cm, and single point charge quality of 27 - 60 g） and full-length detonating cord arranged along the bag. Meantime,the measures of putting sand bags and water hags on beam surfaces to control dust,cutting stirrups of beams,and covering flexible protection net were used as well,all which led to realize low cost and accurate green blasting demolition.