软岩隧道近距下穿敏感建筑物的光面爆破减振施工方案

Smooth Blasting Vibration Reduction Construction Scheme of Soft Rock Tunnel Under-passing Sensitive Buildings at Close Distance

依托杭绍台铁路软岩隧道爆破工程,针对下穿敏感建筑物对隧道爆破振动控制要求极高的特点,通过试验段振动测试结果,分析了三台阶法爆破开挖方案面临的高风险。详细阐述了双侧壁导坑法光面爆破减振施工方案,并重点对左右两侧导坑及中间导坑的掏槽方式、炮眼间距、最小抵抗线、开挖进尺和装药量等参数进行计算取值。现场爆破振动测试结果显示,双侧壁导坑法光面爆破减振施工方案的实测地面爆破峰值振动速度为0.21~1.46 cm/s,减振效果显著,既满足了建筑物的振动控制要求,且光爆效果良好。

Based on the blasting engineering of the soft rock tunnel of Hangzhou-Shaoxing-Taizhou High-speed Railway,targeting the feature that under-passing sensitive buildings has high vibration control requirements on tunnel blasting,from test section vibration test results,the high risks faced with three-step method blasting excavation scheme are analyzed.The construction scheme of vibration reduction of smooth blasting with double sidewall heading method is elaborated.Parameters such as the cutting method,blasting hole spacing,minimum resistance line,excavation footage and charge of the left and right sides and middle drift headings are reasonably and scientifically calculated.Field blasting vibration test results show that double sidewall heading method smooth blasting vibration reduction construction scheme can control the on-site ground blasting peak vibration velocity between 0.21 cm/s and 1.46 cm/s.Vibration reduction result is evident,which not only meets the vibration control requirements of the building,but also has good smooth explosion effect.