大断面隧道穿越水库泄洪渠施工技术研究

摘要

南龙铁路资坑隧道下穿资坑水库泄洪渠，为浅埋、富水、软弱土层地段，施工困难，风险极高，施工过程中，采用地表注浆加固地层止水，水平定向旋喷桩管棚植入结合Ⅱ型超前小导管超前支护，通过综合加固围岩、优化施工工法、三分断面形式、调整施工设备等措施，顺利穿越了复杂地层，有效提高了施工进度。%The Zikeng Tunnel of Nanlong Railway going down through the spillway of Zikeng reservoir.It is located in the place where is either shallow buried,water-rich or soft-soil,which leads to its high risk and construction difficulties.Dur-ing the construction process,by using surface grouting sealing formations,horizontal directional jet pile pipe roof implanta-tion combing with model II leading small pipe advance support and through comprehensive reinforcement of surrounding rock,construction method optimization,three-section form as well as some measures like adjusting construction equipment, we finally smoothly get through the complex formation and effectively improve the construction schedule.