繁华城区浅埋大断面隧道减震爆破技术

Shock absorption techniques for the blasting excavation of a shallow tunnel with large cross-section in urban area

文章以重庆轻轨较新线临江门车站隧道为例,介绍了复杂条件下城市浅埋硬岩特大断面隧道减震爆破的施工方法。开挖爆破中由于采用了一系列综合减震措施,使其对隧道周边围岩的影响降低到了最小程度;在爆破设计中,掏槽眼增加了减震孔,周边眼增加了导向孔,并采取隔孔装药方式,对提高炮眼利用率起到了良好的作用。监测结果表明,爆破震速控制较好。

The paper takes the Linjiangrnen station tunnel on Chongqing Jiaoxin light railway as an example, describes the shock absorption techniques applied to a shallow tunnel with super- large cross- section in urban area embedded in hard rocks under complicated conditions. Comprehensive shock absorption techniques were adopted in the process of excavation which decreased the shock influence on surrounding rock to the least extent. In the design of blasting pattern, relieving holes were added into the cut, guiding holes were added to the relievers, explosive were charged in the alternate holes. Results of monitoring indicated that the blasting vibration was well controlled.