高海拔铁路隧道斜井机械化配套与快速施工

Mechanized Matching and Fast Construction Technology for Inclined Shafts in High-Altitude Railway Tunnels

为解决高海拔高寒地区斜井施工存在气压低、含氧量低、温差大、严寒干燥等问题,以某高海拔铁路隧道斜井工程为背景,结合围岩等级、断面大小、海拔高度,根据斜井施工机械化配套原则,提出高海拔陡坡长斜井机械化安全快速进洞施工工法,并选配超前支护、钻爆、装运、喷锚支护、衬砌等机械化作业线的成套设备。基于高度机械化的设备配套,提出“快挖、快运、快支”的高效施工技术以及各工序快速衔接工艺。以控制围岩变形为核心,构建一套积极干预加固围岩、注重早期支护并快速闭合的主动支护体系。结果表明:与普通钻爆法施工相比,采用三臂凿岩台车高度机械化配套施工效率高,月最快进尺为180 m,较人工钻爆法施工月进尺为130 m相比提高了近30%,施工质量稳定,作业人员投入少,且拱顶沉降和周边收敛均小于规范要求值,衬砌强度可靠,可实现高海拔小断面隧道“快挖、快支、主动支、快封闭”。

The construction of inclined shafts in high-altitude tunnels within cold regions presents significant challenges,including low air pressure and oxygen levels,considerable temperature variations,and extreme cold and dry conditions.To tackle these issues,a case study is conducted on the Longbagou inclined shaft of a plateau railway tunnel.The authors introduce a mechanized matching principle for inclined shafts,taking into account the surrounding rock grade,section size,and altitude.Consequently,a safe and efficient mechanized construction method is developed,particularly suited for inclined shafts with steep slopes in high-altitude areas.This method involves the selection and deployment of a complete range of mechanized equipment for advance support,drilling and blasting,transportation,spray anchor support,and lining.Efficient construction techniques that include rapid excavation,transportation,and support,alongside swift integration of various processes are proposed.Central to this approach is the management of surrounding rock deformation,around which a proactive support system is constructed,emphasizing early intervention in rock reinforcement,early support,and rapid sealing.The findings reveal that,in comparison to traditional drilling and blasting methods,the advanced mechanized construction,facilitated by a three-boom rock drilling jumbos,significantly enhances construction efficiency(achieving a maximum monthly advance of 180 m,which is 30%greater than traditional methods),improves construction stability,reduces the number of operators required,and ensures appropriate lining strength.Furthermore,the crown settlement and peripheral convergence are maintained within acceptable limits,thereby enabling the rapid excavation,support,and sealing of small-section high-altitude tunnels.