Study On The Dynamic Response And Influence Zone Of High-Speed Train Loading Forec On Crossing High-Speed Railway Tunnel

With the rapid development of high-speed railway construction in China, more and more crossing high-speed railway tunnel are currently being built, In order to meet the high standards of high-speed trains running in the tunnel, more and more requirements were set for the dynamic stability and safety of the lining structure of the tunnel. Therefore, the dynamics of the high-speed railway tunnel structure have become increasingly prominent. According to the dynamical problems of the crossing high-speed railway tunnel under the high-speed train loading, This dissertation systematically study the dynamic response characteristic of crossing high-speed railway tunnel, and present the division method of influence zone. This dissertation is granted from the Basic Research Development Program of High-Speed Railway(NO:U1134208). The main research contents and conclusions are as follows:(1) According to the vibration theory of tunnel-rock system, the loading spectrum of high-speed railway and the characteristic of high-speed railway crossing tunnel structure, the numerical model was designed and builded, and the results of numerical calculation was compared with the data of existing research results, to verify the reliability of numerical calculation.(2)Analysised the propagation law of the train loading in the rock pillar from the aspects of acceleration and dynamic stress, and analysised the influence of rock pillar dynamic response by different rock pillar height.(3)Analysised the dynamic response characteristics of crossing tunnel from displacement, acceleratin and stress, and compared with the static equilibrium state of crossing tunnel, then obtained the absolute value and relative value of the incremental of crossing tunnel dynamic response.(4)According to the dynamic response of crossing tunnel, analysised the influence of rock level, train speed, the way of train through, crossing angle and rock pillar heigh from the aspect of displacement, tensile stress and compressive stress of lining structure.(5)Proposed the partition standard of crossing tunnel dynamic response, obtained the fitting function of tensile stress of crossing tunnel lining strecture on multiple factors, then divided the influence zone of crossing tunnel dynamic structure combined with the partition standard and stress function.