瓦斯隧道岩溶与煤系交叠地段超前探测技术研究

Research on the Advanced Detection Technology in the Overlapping Section by Karst and Coal Seam of Hejiapo Gas Tunnel

超前探测技术是隧道穿越复杂地层安全施工的重要前提保障,本文以何家坡瓦斯隧道岩溶与煤系交叠地段为工程背景,制定了“地质雷达初探+超前钻孔精探”的超前地质预报方案,并在何家坡隧道右洞YK42+057~YK42+000区段进行了工程实践。探测结果预测出掌子面前方4~10m与28~44m两个区段范围内存在溶腔发育,并根据孔内瓦斯浓度评定该区段为微瓦斯工区段落。

The advanced geological prediction technology is a key factor for the safe construction of tunnel excavation through the complex strata.This paper focused on the background of the overlapping section by karst and coal seam of Hejiapo gas tunnel.The advanced geological prediction proposal was optimized,which applied ground penetrating radar to conduct survey firstly and then used the method of drilling to detect precisely.This proposal was put into practice in Hejiapo tunnel.It's indicated that there exist karst caves during two sections of 4~10m and 28~44m before the palm face.What's more,this section was assessed as tiny gas work area.