Study On The Geosphere Sensitivity And Structure Adaptability Of The Interchange Tunnel

With the construction of a large number of underground engineering, interchange tunnel project is also in large numbers, which crossing engineering on the existing tunnel safety formed a severe test, become the highest level risk of a city urban tunnel construction. Existing research is mainly carried out research on specific projects, is the lack of systematic research for the interchange tunnel, therefore, for the construction of the main environmental sensitive point Interchange proceeds tunnel "geosphere sensitivity" and structural studies on the adaptability of the system is necessary, to improve and promote the development of significant underground road construction technology.In this paper,took the Chongqing Municipal Science and Technology personnel training program(leading talent) project "Study on the geosphere sensitivity and Adaptability of the structure of urban underground road" as background, the use of mathematical systems theory of sensitivity analysis combined with elastic-plastic mechanics,finite element theory derivation Interchange tunnel obtained univariate sensitivity formula to calculate finite element simulation, data research tools for different depths and different rock conditions, different thickness conditions of interchange tunnel project carried out a systematic study of mechanics and draw the appropriate sensitivity engineering, on this basis for the corresponding adaptive analysis of the structure for the corresponding sensitivity threshold..The main research contents of this paper are as follows:①For eleven provinces and hundreds of domestic tunnels detailed investigation.②Using the sensitivity analysis of mathematical theory of system analysis method combining the theory of elastic-plastic mechanics, the finite element theory, derived the interchange tunnel single factor sensitivity formula.③According to survey results, the establishment of a different depth, different rock conditions, the three-dimensional finite element model interchange tunnel under different conditions, a total thickness of 120 groups through the new tunnel crossing the existing tunnel mechanical and sensitivity studies.④Based on finite element model calculation results, and with reference to theJapanese railway tunnel adjacent construction guidelines and "railway tunnel construction norms"(TB10304-2009), starting from a stable structure, in order to influence the new tunnel to the existing tunnel stress increased allowable value basis,the system obtained reasonable thickness at different depths and different rock conditions tunnel overpass new tunnels and existing tunnels for the future through the new tunnel under the overpass tunnel existing tunnel design and construction to provide a reference;starting from a stable structure to the new influence of stress on the existing tunnel tunnel allowable increase value reference, the previously calculated sensitivity sensitive area divided into strong, weak sensitive area, non-sensitive zone.⑤Based on the text of the sensitive area above the sensitivity threshold of the front,according to the survey results to develop appropriate structure adaptive computing model, obtained the corresponding sensitivity of the model.⑥According to the actual effect of adaptive strategies to reduce the sensitivity of the adaptive strategies sensitive areas in accordance with the strong and weak sensitive area classification for the new interchange tunnel through the tunnel in a particularly sensitive area of the existing tunnel operating conditions chosen to provide adaptive responses reference, to avoid subjective judgments wrong.