薄壁钢筋混凝土烟囱和水塔定向爆破拆除

结合某薄壁钢筋混凝土烟囱和水塔的定向爆破拆除,提出了确保定向爆破安全、成功的几条重要技术措施:①爆破切口圆心角可减小到208°;②在后支撑中心点加钢斜腿支撑,既增大了抵抗烟囱的下坐支撑力,又克服了烟囱的后坐力;③采用“<”形锐角定向窗切口,使定向窗端部受力更均匀;④首次试用快干水泥堵塞炮孔,有效防止了浅眼爆破的冲炮;⑤采用砂包墙埂作飞石防护屏障,既彻底阻挡了飞石,又屏蔽了爆破声响。最终爆破效果相当完美。

DIRECTIONAL BLASTING DEMOLITION OF CHIMNEY AND WATER TOWER BUILT IN THIN REINFORCED CONCRETE WALL

Based on the directional blasting in demolition of a chimney and water tower built in thin reinforced concrete some key technological measures were put forward for the safety and success in directional blasting.These measures include: ①cutting down the blasting incision central angle to 208°;②tilting steel brace sustain at the center of rear strutting section,resulting in an enhancement in resistance force to chimney both fall down and recoil;③adopting the cut in "<" shape for the angle of direction windows,so as to the ends of direction windows suffer stress more evenly;④using fast-setting cement as stemming to avoid effectively burst out of short blast-holes;⑤using wall built in sand-bags as defense against blasting splashing stones to obstruct both blasting splashing stones and blasting sound.The blasting was very wonderful through using these measures.