松散地层管棚预支护效果的数值模拟研究.pdfVIP

Subject ：Numerical Simulation Study on the Performance of Pipes for Reinforcing Tunnel Roof in Loose Strata Specialty ：Geotechnical Engineering Name ：Liu Yongxing (Signature) Instructor ：Dai Jun (Signature) Wang Jianxun (Signature) ABSTRACT Road tunnels, railway tunnels and subway tunnels and other works often encountered loose strata. In order to prevent tunnel excavation affect the surface of buildings or cause large deformation of stratum, we should use pipe roof reinforcement measures to reinforce the surrounding in the front side of tunnel, it is an effective method in common use. Therefore, research on this technology is necessary. Pipe roof reinforcement technology in common loose strata tunnel is researched specifically in this paper, and numerical simulation analysis is combined with projects to find reasonable and efficient pipe roof reinforcement method. The main contents and conclusions are as follows: (1) The concept of loose strata, surrounding rock failure mechanism and mechanical properties of the surrounding, deformation characteristics of surrounding, reinforcement methods are analysed and discoursed. Pipe reinforcement can effectively control the excavation of the front side loose broken strata, it can improve the strength and stability of tunnel surrounding rock, it is an effective reinforcement method. (2) Researched on the construction methods ,classification, and application of the pipe roof, and the characteristics of the pipe roof support in loose formation is analysed