Study On Stress Rule Of Secondary Lining Of Road Tunnel In Cold Regions Of Caverns In Arch

Along with the national infrastructure in the western alpine region has investedheavily in cold regions highway tunnel construction in recent years had made greatprogress. Geological and climatic conditions, the quality of design and construction,operation and maintenance measures a variety of factors, many cold region tunnelsoperating with varying degrees of disease. Which voids behind the lining is oneimportant reason for the cold region tunnels disease.In this paper, the numerical simulation method focuses on cold regions tunnel archlining behind the dome hole in the freeze-thaw process of surrounding rock of tunnelsupporting structure mechanical behavior. The study takes into account the temperaturefield and stress field coupling, empty stagnant water status, hollow shape and size, thesituation of the surrounding rock strength and water content, lining stiffness andthickness and other factors, and calculated using the finite element strength reduction intunnel supporting structure the safety factor under different conditions, analyze summedlining dome behind the empty tunnel supporting structure in cold regions studied.Considering the cold region tunnels lining the cavity behind the complexity of theresearch, this paper numerical simulation analysis of influencing factors of the workingconditions are divided into two categories: one is to empty their own conditions, such aswhether water frost heave, shape and size; and the other the case of external conditions,such as the physical characteristics of surrounding rock, frost heave rate, lining stiffnessand thickness. For the influencing factors, except for separate analysis, and otherinfluences cross-comparative analysis, in order to affect the law and the impact of acomprehensive and in-depth analysis and evaluation of various factors. For each of theabove influencing factors, we have established a two-dimensional elastic-plasticanalysis model to calculate the conditions of tunnel surrounding rock stress field,displacement and temperature fields, focusing on analysis of tunnel supporting structureand the lower part of the hollow Deformation Analysis of the lining segments andcalculate the factor of safety of the structure to the impact coarsely quantized.Founded a large number of analysis and comparison of the calculation results: thetop of tunnel empty water frost heave can seriously distort the lining of the stress state,but only in the vicinity of the dome. Only when larger size will significantly reduce the overall stability of the lining; freezing process of surrounding rock, rock level, liningstiffness and thickness of the external conditions such as the lining of the Forces moreobvious, but almost disturbance less than the lining of the deformation. Lining the forceand deformation of surrounding rock frost heave a positive correlation between the mostobvious changes among almost linear relationship. In addition, the top of tunnel holehas little effect on the temperature field around the tunnel periphery of the hollowmeters away almost to ignore.