高压富水软弱接触带隧道综合处治关键技术研究

Research on Key Technologies for Comprehensive Treatment of Tunnels in High-pressure Water-rich Soft Contact Zone

基于复杂的工程地质条件及施工现状,通过深化地质、工程调研等手段,创造性的提出了钻孔注浆+水平旋喷+长管棚的长距离多维度超前加固方案,并对衬砌及支护参数进行了适应性研究,现场应用取得了成功。研究表明:a.针对多种岩性不整合软弱接触带突涌处治,应结合地层岩性、岩体物性参数、地下水、不良地质体空间分布特征等采用综合加固方案;b.围岩荷载是制定衬砌结构及支护参数的基础,可利用洞内突涌体力学平衡状态进行分析确定;c.水平旋喷桩加固厚度超过3 m时,增加加固圈厚度对于控制围岩变形效果不明显;d.全环型钢钢架+拱墙格栅钢架砼联合支护初期支护体系,以及变截面钢筋混凝土二衬结构,能够保障隧道运营安全。

This paper based on complex engineering geological conditions and construction status,through deepening geology, engineering research and other means,the long-distance multi-dimensional advanced reinforcement scheme of drilling grouting+horizontal rotary-spray+long pipe shed was creatively proposed, the adaptability of lining and support parameters was studied, field applications have been successful. Research shows:1)Acute treatment of multiple lithological integrated soft contact zones,a comprehensive reinforcement scheme should be adopted based on the lithology of the formation, the physical parameters of the rock mass,the spatial distribution characteristics of groundwater and the adverse geological body.2)The surrounding rock load is the basis for the development of lining structures and supporting parameters,the mechanical equilibrium state of the surging body in the cave can be analyzed and determined.3)When the reinforcement thickness of the horizontal rotary blast pile exceeds 3m, increasing the thickness of the reinforcement ring has no obvious effect on controlling the deformation of the surrounding rock.4) Adopting full ring steel frame+arch wall grille steel frame concrete joint support initial support system and variable section reinforced concrete two-liner structure can ensure the safety of tunnel operation.