地基爆破对下伏隧道影响的数值模拟分析

以福州某隧道工程为背景，运用Midas有限元软件模拟地基爆破对下伏既有隧道的影响，从二衬爆破振动速度、内力、最大主应力等角度分析其影响，并对其安全性进行了验算。研究结果表明:地基爆破引起下伏隧道振动速度最大值位于拱顶处，有向四周逐渐减小的趋势；隧道二衬截面混凝土最大主应力和安全系数最小值均位于车行横洞与右洞相交界处。

Numerical Simulation of Foundation Blasting Effect on Underlying Tunnel

Taking a tunnel engineering in Fuzhou as the background, the effect of the foundation blasting on the existing underlying tunnel was simulated with Midas finite element software, and then analyzed from the aspects of the blasting vibration velocity, internal force and maximum principal stress of the secondary lining; furthermore, the safety was checked by calculation. The result shows that the vibration velocity of underlying tunnel caused by foundation blasting peaks at the vault, and tends to gradually reduce around; both the maximum principal stress and the safety coefficient at the section of secondary lining bottom at the intersection of transverse hole for cars and the right hole.