青岛富水砂层隧道工程难点与关键技术研究

Engineering Difficulties and Key Technology Research of Water-enriched Sandy Stratum in Qingdao

选取2个富水砂层区间为工程背景,采用理论分析、现场监测的方法,对管井降水、超前小导管、全断面注浆、水平旋喷桩等关键技术进行了研究。研究结果表明:通过采取区间降水的方法,基本保证区间无水的施工环境,降水后对地层加固方法进行了优化,由全断面注浆变为了超前小导管的注浆方法;未降水的区间采取了水平旋喷桩的注浆方法,通过改进施工方法有效解决了桩体施工角度的控制难、桩间渗水问题。

Based on two interzone in water-enriched sandy stratum tunnel as the background,the methods of theoretical analysis and field monitoring were adopted,to do research on dewatering technology,advanced small catheter,full face grouting,horizontal jet grouting pile. Research results show that construction environment becomes dry by dewatering technology,the layer strengthening measures become the advanced small catheter after dewatering,instead of the full face grouting.Layer strengthening measures of no-dewatering interzone is the horizontal jet grouting pile. The construction angle of pile and the seepage trouble between piles are solved by improving construction method.