川藏铁路千米级水平孔绳索取心钻进技术与应用

Application of the Drilling Technology Based on Wireline Coring to a Kilometer-Level Horizontal Holeon the Sichuan-Tibet Railway

川藏铁路地处青藏高原东部高山峡谷地区,传统垂直钻孔勘探难以满足工程沿线深埋大隧道的勘探需求,采用水平孔取心钻进可以很好地解决这个问题。通过优选钻进设备与工具,制定合理的钻进工艺与泥浆技术措施,形成了一种千米级水平孔绳索取心钻进技术,成功应用于川藏铁路卡子拉山一号隧道水平孔,完成了1212 m水平绳索取心定向钻孔施工任务,查明陡倾岩层3条断层和19处节理破碎带,全孔平均岩心采取率高达97.76%,钻孔各项指标优良。实践证明,千米级水平孔绳索取心钻进技术能够满足川藏铁路深埋大隧道的勘探需求,直观查明隧道洞身段地层岩性、陡倾岩层构造、水文地质条件等情况,为铁路勘查设计提供地质支撑。

The Sichuan-Tibet railway is located in the alplne valley area of eastern Tibetan Plateau,where traditional vertical drilling cannot meet the exploration needs of deep and large tunnels along the project.To tackle this problem,the horizontal drilling is a proper choice.This technology optimizes drilling equipment and tools,formulating reasonable drilling techniques and mud technical measures,thus generating a kilometer-level horizontal wireline coring drilling,which was successfully applied to a horizontal hole of the Kazila Mountain No.1 tunnel on the Sichuan-Tibet railway.It completed a directional drilling task for 1212 m horizontal rope coring,and clarified three faults and 19 joint fracture zones in steeply inclined rock formations.The average core recovery rate of the whole hole was as high as 97.76%,and every drilling indicators were excellent.The practice has proved that this kilometer-level horizontal hole rope coring drilling technology can meet the exploration needs of deep-buried large tunnels on the Sichuan-Tibet railway,permitting to intuitively investigate the stratum lithology,structure of steeply inclined rock formation,hydrogeological conditions and other conditions of the tunnel body section,providing a geological support for railway survey and design.