钢筋砼支撑梁爆破拆除新技术及应用

New Blasting Demolition Technology and Its Application in Reinforced Concrete Support Beam Engineering

复杂环境下深基坑钢筋混凝土支撑梁的安全、高效拆除是城市建设过程中极为关键的环节。基于箍筋对支撑梁侧向约束作用机制的理论分析,揭示解除箍筋侧向约束效应前后梁内砼单元应力状态的演变规律及对支撑梁爆破效果的影响,并研发新的支撑梁线性切割预处理方法、布孔方法及其毫秒延时起爆网路,形成较为系统的支撑梁爆破拆除技术。工程应用结果表明,支撑梁线性切割预处理方法可显著增强拆除效果;多向协同布孔法可改善爆炸能量耦合状态,减小爆破飞石危害;基于爆破网路连接单元的毫秒延时起爆网路可有效控制振动强度,提高网路可靠性。

Safe and efficient demolition of reinforced concrete support beam in deep foundation pit under complex environment is a key point in the process of urban construction. On the basis of theoretical analysis on lateral restraint mechanism of stirrups,the evolution law for the stress state of the concrete element and the blasting effect of the supporting beam is revealed before and after the remove of the lateral restraint effect of the stirrup. The methods for stirrup cutting,shothole arrangement and millisecond delay initiation network are developed. A comparatively systematic technology on blasting demolition of support beams is formed. The result of engineering application shows that,the blasting demolition effect can be significantly enhanced by the linear cutting pretreatment method. The coupling state of explosion energy can be improved and the hazard of blasting flying rocks can be reduced by the method of multi-directional synergy arrangement of shotholes. The vibration intensity can be effectively controlled and the network reliability can be improved by the millisecond delay detonating network based on the blasting network connection unit.