隧道Ⅴ级围岩喷射混凝土衬砌厚度数值分析

Numerical Analysis on the Shotcrete Lining Thickness of Class-V Surrounding Rock in Tunnels

喷射混凝土作为新奥法施工的三大必须手段之一,对洞室围岩起到支护的作用,其中喷射混凝土衬砌的厚度对围岩支护效果影响较大。本文针对公路隧道Ⅴ级围岩进行UDEC数值模拟,分析不同喷层厚度对围岩稳定性的影响。结果表明,对于Ⅴ级隧道围岩,要采用钢拱架、钢筋网、锚杆和喷射混凝土联合支护,且喷射混凝土厚度为25cm时,支护效果最好。研究结果为隧道初期支护施工设计提供了科学依据和参考。

As one of three essential means of the new Austrian method constructional, the shotcrete construction plays a supporting role in the surrounding rock, and the shotcrete lining thickness has a great effect on the supporting effect of the surrounding rock. The UDEC numerical simulation for Class-V surrounding rock in tunnels is taken to analyze the influence of different shotcrete thickness on the stability of the surrounding rock. The results show that for Class-V surrounding rock in tunnels, when using the steel arch, steel mesh, bolt and shotcrete for combined support and shotcrete thickness is 25 cm, the supporting effect is best. The results provide scientific basis and reference for initial supporting construction design of the tunnel.