水封爆破在软弱围岩隧道台阶法开挖中的应用研究

Study on Application of Water Blasting in Bench Excavation of the Tunnel with Weak Surrounding Rocks

软弱围岩隧道中采用钻爆法开挖,可形成光滑的开挖轮廓并减小爆破扰动,对提升隧道施工效率以及保证施工安全性至关重要。依托哈牡专线威虎山隧道,研究了水封爆破在软弱围岩隧道台阶法开挖中的应用,对比了常规爆破与水封爆破的超欠挖以及振动安全控制效果。研究结果表明,在软弱围岩隧道台阶法开挖中,采用水封爆破更有助于形成光滑的开挖轮廓,降低了爆破诱发振动;相比常规爆破,水封爆破更适用于软弱围岩隧道开挖。

In the tunnel with weak surrounding rocks,that a smooth excavation profile formed by drilling-blasting method will reduce blasting disturbance is essential to improve tunneling efficiency and ensure construction safety.In this paper, based on the Weihu Mountain Tunnel, the application of water blasting in bench excavation of the tunnel with soft rock mass were studied. Then, overbreak and underbreak and the vibration control effect of conventional blasting and water blasting were compared. The results indicate that the water blasting is more beneficial to create a smooth excavation profile and reduce blasting vibration and is more suitable for tunnel with weak surrounding rocks excavation.