水平模袋桩在隧道进洞口注浆加固中的应用

Application of Horizontal Mold Bag Pile in Grouting Reinforcement of Tunnel Entrance

为了解决常规隧道进洞口注浆加固工艺中浆液扩散控制难等问题,展开水平模袋桩工艺在隧道进洞口加固工程中的应用研究。系统研究水平模袋桩加固机理,分析其优势特点。结合青岛市红岛—胶南城际轨道交通二期工程香江路站进洞口不良地质加固工程,应用水平模袋桩工艺进行注浆加固。结果表明,模袋桩超前支护结构与隧道超前注浆加固体相互配合,将在隧道拱顶地层形成“刚性支撑+挤密固结+注浆加固体”复合加固体。水平模袋桩不仅起到类似管棚的支护作用,有效抑制了围岩松动,提高了地层稳定性,而且对目标层具有挤密效果,有效控制了浆液扩散范围,取得了较好的加固防渗效果。

In order to solve the problems of grouting diffusion control in the conventional tunnel entrance grouting reinforcement process, the application research of the horizontal mold bag pile technology in the tunnel entrance reinforcement project is developed. The reinforcement mechanism of horizontal mold bag piles is studied systematically, and its advantages and characteristics are analyzed. Combined with the poor geological reinforcement project at the entrance of Xiangjiang Road Station in Qingdao Hongdao-Jiaonan Intercity Rail Transit phase II project, horizontal mold bag pile technology is used for grouting. The results show that the advanced support structure of the molded bag piles and the advanced grouting and solids of the tunnel will cooperate to form a “rigid support + compaction consolidation + grouting plus solids” composite solids in the tunnel arch stratum. The horizontal mold bag pile not only plays a supporting role similar to the pipe shed, effectively restrains the surrounding rock loosening, improves the stratum stability, but also has a compaction effect on the target layer, effectively controls the slurry diffusion range, a better effect of reinforcement and seepage prevention is achieved.