Pier Stability And Reliability Analysis Of Continuous Rigid Frame Bridge During Construction

The remarkable development of prestressed concrete continuous rigid frame bridges has taken place in recent years, The construction failure probability of pier has been changed according to the stage. Rigid frame bridge of the failure probability is larger than stipulating in the uniform standard, research on the failure probability of the continuous rigid frame bridges during the construction is necessary. Taking the Heilong bridge on the Rucheng section of Yanru speedway as the practical engineering background, Construction of stability and reliability analysis has been made for high pier and long span continuous rigid frame bridge maximum cantilever stage. Specific researches are as follows:(1) The strength and service limit state equations of reliability analysis are derived by strictly adhering to the load and capacity formulas and requirements set forth in Chinese highway bridge design specifications, It introduces the basic theory of the engineering structures reliability and the engineering structures of the system reliability calculation method, The reliable indicator was get according to the probability significance of reliability, The calculation accuracy of FOSM method and RSM method are compared.(2) The failure modes of the engineering structure are discussed. It introduced to the structure of the series system, the parallel system and the series-parallel system. The advantages and disadvantages of the reliability evaluation method of engineering structure, including wide range method, narrow bounds method and probabilistic network evaluation technique were summarized.(3) It introduces two types of basic theories of stability about bridge structure are introduced and the thesis indicates most stability problems come up against in practice belong to the second type stability problem, The large finite element software MIDAS/CIVIL was used to analysis the stability about the Heilong bridge by establishing three dimensional finite element model for the maximum cantilever state and the finished bridge state, It has analyzed the effect to the bridge’s stability which separately considered the impact of wind load, suspended wagon dropped and different temperature effect of the sunshine, has obtained the rule how influence to the stable of bridge by each kind of load case.(4) For long and span continuous rigid frame bridges various stages of resistance and load related characteristics, under the mode of the buckling failure, high pier and long span continuous rigid frame bridge of the reliability function based on the stochastic process model is established, Failure mode methods and system reliability search methods has been described. It discusses the randomness of structural resistance, construction loads and construction live loads. According to examples and calculations, The method can effectively analyze the reliability of rigid frame bridge with high pier and long span during construction period. The calculation and analysis processes presented in this paper can provide the reference value to the actual engineering structure.