| In our large-scale construction of the tunnel construction, large deformation of soft surrounding rock tunnel has been plagued by many tunnel builders. The main reason is weak surrounding rock deformation characteristic of tunnel deformation mechanism study other aspects of understanding the many deficiencies, distortion control measures adopted by a certain lack of pertinence. For these series of questions, the paper based on shuangfeng tunnel project of Mu Sui track, with the background of soft surrounding rock tunnel deformation, analysis of the theoretical analysis of soft surrounding rock tunnel. Followed by the actual monitoring and measuring deformation, analysis of control measures proposed and numerical simulation is different.The optimum deformation controls measures. Finally, the use of catastrophe theory analysis shuangfeng tunnel ultimate displacement and deformation shuangfeng build the tunnel control reference, and preferred the results of theoretical analysis and numerical simulation of deformation control measures combined with the results based on three levels of management mechanisms and the widespread use of engineering, summarize the reasonable control measures shuangfeng tunnel deformation. The main work and achievements are as follows:(1) The theoretical analysis of the deformation mechanism of soft rock, including: the concept of soft rock- Geological soft rock and soft rock engineering; classification of soft rock- grading and engineering geological classification; mechanical characteristics of soft rock- the basic mechanics features and characteristics of engineering mechanics; deformation of soft rock failure characteristics.(2) Through on-site monitoring and measuring the actual of the data and supporting structure deformation force that analysis the shuangfeng tunnel. Data analysis showed that the initial deformation of surrounding rock is larger and longer duration; large rock lateral pressure, making the support force structure presents asymmetry.(3) Based on soft rock deformation mechanism and the actual monitoring and measurement analysis, target deformation control measures and comparative analysis of numerical simulation of different variants of control measures, including: the use of different step heights, different step lengths different excavation footage, different locks foot anchor tube as well as different forms such as vertical connections. Preferred results obtained, should adopt the step height 3.4m, 5m length steps, 0.5m excavation footage, on the steps of using a large ramp angle lock foot anchor tubes, down the steps adopted under lock miter smaller foot anchor pipe longitudinal joint is used on the 14 th channel.(4) The using of catastrophe theory can analysis that shuangfeng tunnel ultimate displacement and deformation shuangfeng establish that benchmarks tunnel control mechanism based on the results of three management and engineering in general use.(5) To prefer the results of theoretical analysis and numerical simulation of deformation control measures combined summarized shuangfeng tunnel deformation reasonable control measures. For the reasonable can control measures shuangfeng tunnel deformation, including: construction methods- three steps recommended seven-step excavation method; supporting methods- initial support for shotcrete support, while the auxiliary lock foot anchor pipe and vertical connection. |
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