复杂地质条件巷道探测钻孔施工及防治水技术研究

Research on Drilling Construction and Water Prevention Technology for Detecting and Drilling Complex Geological Conditions in Tunnels

针对21106运输巷掘进区域内水文地质条件复杂的情况,提出采用长距离定向钻孔对顶板含水层进行超前疏排,从巷道掘进前即可降低顶板含水层富水量、水头压力,为掘进创造良好条件。为避免掘进期间围岩出现较大淋水问题,在巷道迎头布置2排探测钻孔,实现顶板及掘进前方一定范围内探测。现场应用后,21106运输巷顶板定向长钻累积疏排水量为1.69万m^(3)、迎头短距离探测钻孔疏排水量为3 690 m^(3),疏排后运输巷掘进期间围岩保持干燥,基本不出现淋水问题。

In response to the complex hydrogeological conditions in the excavation area of the 21106 transportation roadway,it is proposed to use long-distance directional drilling to advance drainage of the roof aquifer.This can reduce the water content and head pressure of the roof aquifer from before the roadway excavation,creating good conditions for excavation.To avoid significant water leakage in the surrounding rock during excavation,two rows of detection boreholes are arranged at the front of the tunnel to achieve detection of the roof and a certain range in front of the excavation.After on-site application,the cumulative drainage volume of the directional long drilling on the top plate of the 21106 transportation roadway was 16900 m^(3),and the drainage volume of the short distance detection drilling on the head was 3690 m^(3).During the excavation of the transportation roadway after drainage,the surrounding rock remained dry and there was basically no water leakage problem.