双层预裂爆破技术在地铁隧道施工中的应用及减震效果分析

Application of Double-layer Pre-split Blasting Technology in Subway Tunnel Construction and Analysis of Damping Effect

为保护地铁隧道工程周边的建(构)筑物和非开挖区域的岩层,以某地铁隧道工程为例,介绍了双层预裂爆破技术的减震机理,分析了炮孔间距、线装药密度、装药结构、起爆网络设计,在地铁紧邻建筑物和被保护结构处设置了震动监测点,使用3向速度传感器和爆破测震仪监测震动数据。结果表明,建筑物处震动速度为3.0~4.0 cm/s,被保护区域震动速度为14.55~23.14 cm/s,均符合《爆破安全规程》的规定,减震效果良好。

In order to protect structures around the subway tunnel project and the rock strata in the trenchless area,through taking subway tunnel project as an example,the study introduces the damping mechanism of double-deck presplitting blasting technology;analyzes the design of hole spacing,linear charge density,charge structure and detonating network design;sets vibration monitoring point in the subway adjacent to buildings and protected structures;and monitors vibration data with 3-way speed sensor and blast seismograph.The results show that speed of vibration at the building is 3.0~4.0 cm/s,and that in protected area is 14.55~23.14 cm/s,which accords with“Blasting Safety Regulation”and has good damping effect.