580 m长钢筋混凝土箱型拱桥爆破拆除

580 m长钢筋混凝拱桥需爆破拆除。大桥是钢筋混凝土建造,拱肋采用箱型截面的砼箱形拱桥,经多次加固,桥墩最大体积1200 m~3,桥面到墩角最高33 m,拱箱壁为薄壁结构。因传统钻爆方式无法有效破坏大桥结构,采用水压、深孔和浅孔爆破相结合的方式,将药包置于注满水的箱型拱肋内的设计位置上,以水作为传爆介质传播爆炸压力使拱肋破坏,从而达到破坏拱轴解除支撑的目的;对桥墩采用大孔径深孔,由桥面垂直钻孔一次性爆破解除;桥面、拱上结构等用浅孔爆破。大桥解体充分,空气冲击波、飞石及噪声等得到有效控制,也减少了后续出渣工作量。

Explosive Demolition of 580 m Long Reinforced Concrete Box-typed Arch Bridge

A 580 m Long Reinforced Concrete bridge needs explosive demolition. The concrete bridge was arch ribs with box-shaped section,which was reinforced by several times,with the largest pier volume 1200 m3 and the height from deck to pier up to 33 m,and arch box wall with thin-walled structure. The traditional method of drilling blasting cannot effectively destroy its structure. Combined with water pressure,deep hole and shallow hole blasting, the charge was placed in the design position in the box arch rib filled with water,which acted as transmission medium to destroy arch ribs. The large hole drilling method for pier and shallow hole blasting for bridge floor were adapted to demolish the bridge deck and arch structure. The bridge was disintegrated fully,and the air shock wave,fly stone and noise were controlled effectively. In addition,the follow-up slag workload was also reduced as well.