武隆小净距隧道掘进控制爆破技术

针对武隆隧道小净距段爆破施工必须严格控制爆破地震效应的特点,提出了可行的爆破开挖方案,并根据爆破地震效应的实测研究结果分别给出了隧道净距为7~12 m和4~7 m 2种工况的爆破参数和设计图表。所提出的掘进控制爆破技术在施工中的应用表明,爆破方案和爆破参数设计合理,爆破开挖未产生过大的超挖和围岩扰动,有效地保证了隧道围岩的稳定。隧道净距为7~12 m和4~7 m时的振动监测表明,临近后洞掌子面的前洞边墙最大振动速度为16.75 cm/s和12.07 cm/s,满足爆破安全规程的振动控制标准。

Controll Blasting for Neighboring Tunnel Advacement in Wulong Tunnel

In view of the situation that the blasting vibration must be strictly controlled in Wulong neighboring tunnel construction,the excavating scheme wag put forward.Furthermore,the blasting parameters and design charts of interval distance of 7～12 m and 4～7 m were given according to the blasting vibration monitored results.The application of the proposed controll blasting technique shows that the blasting scheme is reasonable,the excavation dcesn't callge the larger overbreak and the surrounding rock disturbance,which assuues the stability of surrounding rock. The monitored results in case ofinterval distance of 7～12 m and 4～7 m shows that the PPV ofthe front tunnel wall close to the work face of the back tunnel are 16.75 cm/s and 12.07cm/s respectively.which agrees with the Safety Regulations for Blasting.