Study On The Stress Analysis And Reliability Of Shield Tunnel Joint Structure Under High Temperature

Abstract:With the rapid development of domestic subway, shield tu nnel construction project also gradually increasing. To security issue s, especially under the fire of shield tunnel structure safety, became one of the hot spot in the existing. Of shield tunnel is composed of segment through joint assembly, in the event of fire, segment co mponent damage happens, not only as a weak link of the stress ch aracteristics of joint structure under high temperature it will do grea t damage to the tunnel structure safety; At the same time, the joint structure is the key of tunnel waterproof, its catastrophe behavior under high temperature, such as excessive deformation of joint lead to leakage, etc., will greatly influence the use function of shield t unnel. Visible, how to determine the heat shield tunnel the stress ch aracteristics of joint structure and on this basis to evaluate the safet y and reliability, is the key to the future of shield tunnel hazard as sessment. So in this paper, the joint structure of shield tunnel under high temperature stress characteristics for the following research:1. The joint structure of three-dimensional numerical model is set up, to determine the fire temperature distributions of joint struct ure, key research local and connecting bolt heating process of high temperature hand hole; Reveal not concentric force, eccentricity loa d combinations under the joint structure of open quantity change ru le; To explore in the process of high temperature bolts and the cha nge of the stress and strain of the concrete structure rule, joint stru cture and analyze the compressive zone height change rule.2. Based on the joint structure temperature stress model, consid ering the influence of the joint structure liner, in combination with the results of numerical simulation, analyzed the seam in the norma1running-assembly-fire under high temperature and the whole p rocess of the mechanical behavior and deformation mechanism; Hig h temperature joint structure model is established, under the high te mperature joint structure joint stiffness calculation method, and acco rding to the result of numerical simulation of temperature field is c alculated, and compared with the results of numerical simulation an alysis, verify the theoretical feasibility of the algorithm.3. Based on the mechanical model of joint structure in high te mperature fire, high temperature joint analysis of shield tunnel struc ture failure modes, failure functions of fire joint structure under hig h temperature is given, and based on combining the checking point method to compute liner thickness, bolt position, lining thickness, t he influence law of different parameters on the joint structure reliab ility; Combined with reliability analysis and the results of numerical simulation, presents the corresponding subway shield tunnel joint fi re prevention advice.