An Initial Study On The Technology Of Mt.Xuefeng Tunnel Adjacent Rock Deformation Monitoring And Back Analysis

Mt.Xuefeng tunnel of ShaoHuai Expressway in Hunan Province is one of the deepest and longest highway tunnel which is in construction. And for the tunnel that built with NATM, field monitoring measuration is the key of the point. This paper combined geology analysis with dynamic analysis of monitoring information, which of these was investigated by the author. All of the information acquired in monitoring is synthetically analyzed in tunnel construction, which made a compact united of geology analysis, circumstance analysis and monitoring information analysis come true. Then take the real-time monitoring information to back analysis by the way of the combination of human and computer in time to achieve the goals of the field construction and optimize the support design.On the basis of above, with the help of my teacher, I refereed the data and experience of Mt.Erlang tunnel, Mt.Zhegu tunnel, Longxi tunnel, and combined with the West Traffic Scientific Research item, the research of construction geology survey in Mt.Xuefeng tunnel, at last I chose "An Initial Study on the technology of Mt.Xuefeng tunnel adjacent rock deformation monitoring and back analysis" as the subject of my paper. This paper mainly researched the following below.(1)The paper dissertated the circumstance of engineering geology comprehensively. And made the statistical analysis on the base of field investigation in correspond tunnel, it contain strata rock character, geology structure, geology disaster, groundwater emergence.(2)Begin with the design and construction idea of NATM, we cooperate and make a systemic study with Chongqing Communication Institute and ChangAn University to layout the monitoring cross-section, choose the monitoring projects, use the devices to monitor the adjacent rock's displacement, operate the correspond devices and inbuilt measuring points.(3)To conclude the experience of TMS in Mt.Erlang tunnel and Mt.Zhegu tunnel on the base of above, combined with the actually circs of Mt.Xuefeng to ameliorate the TMS of which the author made a thorough research in testing principle, facturing, assembling, monitoring, device protection. The author conclude the good points and some defects of TMS(4)The research include monitoring the adjacent rock's surface displacement of Mt.xuefeng, and relatively analysis the accumulating constringency, the rate of deformation, the time of testing and the cross-section embedded depth with geology circumstance. The result goes to : category II adjacent rock stabilize in 30 to 40 days, 20 to 30 days for category III, 10 to 20 days for category IV and about 10 days for category V, select the days each category needs above as the best time of the second lining. Under the situation when unusual variety of the monitoring data was detected, it can be used to predict geological disaster apparent effectively.(5) Do monitoring researches in inside adjacent rock by sectionalize the tunnel; take the advantage of improved TMS to field monitoring to reflect the situation of adjacent rock inside displacement; confirm the loose scope of the tunnel excavation should be less than 3M and, make a comparison with the monitoring data in the same time and on the same cross-section. All of these reflect the situation of the field adjacent rock's deformation truly, and in time.(6)â… emphasize the combination of human and computer to exercise in the tunnel engineering, and conclude the results below, the mechanical parameter have a half difference with it on categoryâ…¡,â…¢adjacent rock while it is more or less the same of categoryâ…£,â…¤adjacent rock's mechanical and design parameter by the way begin with geology investigation, introduce a way of classical analogy analysis, and make use of programs BMP90, BMP2000 to back analysis the classical cross-section. At Iast, in considering the realistic situation of the geology,â… adjust the mechanical parameter of categoryâ…¡,â…¢adjacent rock by reference relevant experience parameter and, keep categoryâ…£,â…¤adjacent rock's mechanical parameter fixed.(7) The paper combines with the analysis conclusion and field geology investigation, and keeps in accordance with the unit of design, construction, and supervision and, adjusts the adjacent rock of the east entrance to the left tunnel of Mt. xuefeng.