| The cable-stayed bridge is a high-order statically indeterminate structural system,and its construction must undergo multiple system transformations,and its mechanical state is very complicated.The unsymmetrical single-tower cable-stayed bridge has the problem of unbalanced moments on both sides of the main side span,which makes the mechanical state of this type of cable-stayed bridge in the bridge operation stage and the plane rotating construction process more complicated,and successfully analyzes the entire structure The state of phase mechanics is a prerequisite to ensure engineering safety.This paper takes the cable-stayed bridge of the main bridge of Kunshan West Road-304 National Road in Shenyang City as an engineering example,combining engineering mechanics theory,finite element method,influence matrix method and unstressed state control method to analyze the mechanical state of the engineering structure,and the optimization is obtained.The cable force value of the completed bridge and the reasonable construction state,and check the anti-overturning stability of the rotating construction.The specific content and methods are as follows:The Midas/Civil software establishes the finite element numerical model of the bridge state of the engineering example,calculates the initial tension of the cable from the bridge cable force of the original design drawing,and substitutes it into the model to verify whether the model is reasonable.The related influence matrix is derived from the model analysis structure.The Matlab software establishes the secondary optimization function of the cable tension at the bridge completion stage.The penalty function method and the differential evolution algorithm solve the function to obtain the initial tension of the cable,which is substituted into the numerical model to obtain the final result.For the bridge cable force,compare the cable force with the original design cable force corresponding to the model analysis state(the overall internal force distribution of the structure and the stress displacement of the main components)to verify whether the optimization is reasonable and whether the method is feasible.The Midas/Civil software establishes the finite element numerical model of the plane swivel cantilever state of the engineering example,and solves the cable force value that meets the construction stage;the Midas/Civil software establishes the finite element numerical model of all the construction stages of the engineering example,the formal analysis model,and applies the stress-free state control method,Set the cable force in the cantilever state of the plane swivel as the target,determine the initial construction tensile force of the structural stay cable,and use the cable force at the completion stage as the target cable force to determine the secondary construction tensile force of the structural stay cable,and substitute it into the construction stage model for formal analysis,Check and calculate the force and deformation of the structure in all construction stages to ensure the safety of the structure in the construction stage,and calculate the main beam erection model elevation from the main beam deflection in the final construction stage.It proves that the analysis method in the construction phase of this paper is feasible.Introduce the composition of the spherical hinge system of the cable-stayed bridge and the checking calculation method of its anti-overturning stability.Apply the static wind load theory to calculate the equivalent static gust load to the spherical hinge system lateral and longitudinal overturning moments;apply the finite element model to analyze and calculate The superstructure eccentrically opposes the lateral and longitudinal overturning moments of the spherical hinge system;the current anti-overturning theory of the spherical hinge system is used to calculate the anti-overturning moment and check the stability,and check whether the designed balance weight of the bridge superstructure meets the balance condition from the result of the verification.. |
