180m钢筋混凝土烟囱两段单向控制爆破拆除

摘要

介绍了苛刻条件下180 m高钢筋混凝土烟囱不能采用整体定向爆破和双向折叠爆破,仅能采用两段单向控制爆破拆除的成功案例.为了避开烟囱烟道口的不利影响,解决倒塌空间受限问题,通过在烟囱+90 m和+21 m高度处布设高位切口,上下切口分别采用倒梯形和正梯形切口设计,定向窗角度分别为30.96°和29.74°,上、下切口圆心角分别为205.4°和207.5°,切口高度分别为2.5m和3.6m,钢筋混凝土烟囱分两次、分两段爆破,确保了烟囱按照设计方向倒塌并有效控制了烟囱后座.通过开挖减振沟、倒塌区域铺设缓冲垫层和采取相应防飞石措施,有效控制了烟囱倒塌触地振动和飞石飞散距离.两次爆破均取得了良好的爆破效果,达到了安全、精细爆破拆除的目的,可为今后复杂环境下高耸烟囱爆破工程提供参考.%Owing to the strict surrounding,the two section and same direction blasting technology is chosen as the explosive demolition method for a 180 m high reinforced concrete,where the integral directional blasting or bidirectional folding blasting cant be applied.In order to avoid the adverse effects of chimney flue mouth and to solve the problem of limited space,the collapse direction and backseat of the chimney are controlled by disposing high position incision in height of 21 m and 90 m with trapezium and inverse trapezoid,respectively,where The directional window angle is set as 30.96 and 29.74 degree.The incision central angle is 205.4 and 207.5 degree and the notch height is 2.5 m and 3.6 m,respectively.The chimney collapse touchdown vibration and distance of flyrock effectively are controlled by excavating ditch and laying cushion on the collapsed area.The two explosive demolitions of chimney get good blasting effect.