Determination Method Of Reasonable Finished Dead State On CFST Tied Arch Bridge

At present, the CFST arch bridge design code of highway transportation has not been promulgated. Scientific researchers, designers have not yet formed a unified understanding on design and calculation method of CFST tied arch bridge, which leads to the design security level of CFST tied arch bridge is different from each other. So, the application and development of CFST arch bridge was hampered by the present design situation. In this paper, whether the whole structure stress is reasonable or not was set to optimization object so as to determine the reasonable finished dead state of CFST tied arch bridge, and form a reasonable finished dead state design method of CFST tied arch bridge, the main research contents are as follows:1. Based on the theory of structural design optimization and principle of least strain energy, the objective function and corresponding constraint expressions were formed, and the three spline function were used to optimize arch axis lineshape, together with the clear understanding of the basic theory and method which are applicable to optimize the reasonable finisheed dead state of CFST arch bridge.2. Aming at the whole structure stress is reasonable, and according to the induction analysis based on the selecting principle and optimization method of CFST tied arch bridge’s reasonable arch axis lineshape, the determination method of suspender and tie bar tension force, the optimization method that is used to determin the reasonable finished dead state of CFST tied arch bridge will be formed.3. As the least strain energy of discrete structures was objective function,unconstrained optimization model were used to simultaneously optimize the suspender and tie bar tension force, and the three spline function were used to optimize CFST tied arch axis lineshape. And at last, a new method, synthesis method, was put forward to determine the reasonable finished dead state of CFST tied arch bridge.4.The synthesis method was used to determine the reasonable finished dead state of the background engineering. By comparising the main component’s internal force under dead load of design and reasonable finished state, it was verified that the synthesis method can be used to determine the reasonable finished dead state of CFST tied arch bridge.