超前地质预报在隧道围岩动态分级预测中的应用

Application of Advanced Geological Prediction in Dynamic Classification Prediction for Tunnel Surrounding Rock

隧道的围岩等级直接影响到施工的开挖方法、支护结构的确定以及隧道的施工安全等诸多方面。在目前的隧道工程中,准确地预测前方围岩的等级仍然是一个重点和难点。以长桥隧道工程为实例,先后采用TGP探测法、SIR-20地质雷达探测法、掌子面编录法3种超前地质预报方法,由远到近,由粗到细地对隧道围岩的等级进行动态预测。实际开挖结果表明:该动态预测方法具有较高的准确性,可以有效地指导隧道安全施工。

The classification of tunnel surrounding rock has a direct impact on the determination of excavation method and the kind of the supporting structure as well as the tunnel＇＇s construction safety and many other aspects.How to accurately predict the surrounding rock＇＇s classification is still an emphasis and difficulty in current tunnel engineering.Taking Changqiao tunnel as an example,three advanced geological prediction methods were applied successively,that is TGP detection,SIR-20 geological radar detection and geological logging method.Therefore,a dynamic prediction of surrounding rock＇＇s classification was carried out from far to near,meanwhile from coarse to fine.Actual excavation results show that the proposed dynamic prediction method has high accuracy,which provides an effective guidance for the safety of tunnel construction.