绢云母石英片岩公路隧道围岩分级研究

在隧道建设过程中,准确的围岩分级对保证隧道施工的稳定性有重要意义。通过对典型绢云母石英片岩隧道岩石样本进行分析,得出与之相适应的BQ优化公式。针对绢云母石英片岩的特性,对BQ分级法中地下水修正系数进行重新考虑;并引入黏土矿物含量的修正指标和软弱夹层的修正指标,对BQ法进行修正,得出修正以后的建议BQ]'值法公式。以在建十房高速通省隧道为例,进行验证分析,得出BQ]'分级法确定的围岩级别与实际开挖揭露围岩级别较相符的结论,可为类似隧道围岩分级提供参考。

Analysis of Surrounding Rock Classification of Sericite QuartzSchist Tunnel

The accurate classification of surrounding rock is significance to guarantee the stability of the construction in the process of tunnel construction. Through analyzing the rock samples of typical sericite quartz schist tunnel, the optimized BQ formula was created. According to the characteristics of Sericite quartz schist, the BQ]' classification method was put forward by modifying the BQ classification method after reconsidering groundwater correction factor, introducing correction factor of clay content and weak intercalation. Based on verification and analysis of the Tongsheng Tunnel on Shifang highway, it was concluded that the rock grade determined by BQ]' classification method is corresponded with the actual rock grade, and this method can provide a reference to surrounding rock classification of similar tunnel.