引水隧洞三岔口平面布置设计与施工稳定性研究

Study on Layout Design and Construction Stability of Diversion Tunnel Junction

【目的】为解决龙潭隧洞2#施工支洞与主洞交叉口地形狭窄、物流组织复杂和施工时相互干扰大,受力复杂,围岩稳定性较差等问题。【方法】提出在主支洞交叉口设置井底转渣车场,详细阐述了井底下沉式无轨有轨立体转换渣场布置总体方案,并通过数值模拟确定施工不利影响区域和应重点关注的工序。【结果】该方案促进了三岔口的安全快速施工,并有效提高了后续隧洞施工的出渣及物料运输效率。【结论】在设有大坡度斜井的隧洞施工中,合理进行井底渣场设置能够解决隧洞施工时物料运输的物流组织问题。隧洞施工时,三岔口隧道围岩变形量较大,故应重点关注三岔口的挑顶施工,并加强对三岔口围岩的支护。

[Purposes]This paper aims solve the problems of narrow terrain,complex logistics organization,large mutual interference during construction,complex stress and poor stability of surrounding rock at the intersection of the 2#construction branch hole and the main hole of Longtan Tunnel.[Methods]It is proposed to set up a bottom-hole slag transfer yard at the intersection of the main and branch tunnels.The overall layout scheme of the bottom-hole sinking trackless track three-dimensional conversion slag yard is elaborated in detail,and the adverse impact area of construction and the process that should be paid attention to are determined by numerical simulation.[Findings]This plan promotes the safe and rapid construction of the junction,and effectively improves the efficiency of slag discharge and material transportation in the subsequent tunnel construction.[Conclusions]In the tunnel construction with a large slope inclined shaft,the reasonable setting of the bottom slag field can solve the logistics organization problem of material transportation during tunnel construction.During the tunnel construction,the deformation of the surrounding rock of the junction is large,so we should focus on the construction of the junction and strengthen the surrounding rock support of junction.