Study On The Proportioning Of Tail Void Grouting Material And Up Floating Control Of Shield Tunnel

With the wide use of shield tunneling method in important underground engineering in our country, it has become a major method applied in city metro construction. During the construction of shield machine, tail void grouting is a necessary and key procedure, which can actively control the tunnel uplift and ground subsidence. This paper aims for the construction of South Xizang Road Tunnel in Shanghai with shield tunneling method, a series of grouting material proportioning tests were carried out. The reasons and control countermeasures were detailed introduced on the basis of the monitoring data of Xiangyin Road Tunnel in Shanghai. The main works of this paper are as follows:1. Investigated and generalized the tail void grouting types, the materials and the grouting mode by home and abroad documents, anlyzed the difference among them.2. Summarized the construction technology and method of tai void grouting. Advanced the calculating method based on deep analysis to the key parameters of tail void grouting construction.3. Analyzed the influence of grouting components on the property of grout based on the proportioning test. Then obtain the parameters of grouting strength, flowability, workability, density, bleeding rate and so on.4. Based on the up flotation problem, discussed the the reasons and mechanism of tunnel uplift.5. Compared the monitoring data with the result of simplified calculation of Xiangyin Road Tunnel. The key factors which influced the tunnel uplift were obtained, then get the contol countermeasures to the tunnel uplift problem.