Analytical algorithm for completed state of suspension bridge based on rigid supported continuous beam method
To solve the problem of calculating and closing the equilibrium state of suspension bridge,an analytical algorithm of completed state of suspension bridge was proposed.First of all,according to the complementary energy theorem,the state objective function of the rigid supported continuous beam was derived and the compression deformation of the tower was considered,nonlinear equations of the cable system was established based on the catenary theory.And then the unstressed curvature of the stiff girder was considered,according to the differential equations of bending deformation of stiffening beams,the nonlinear equations for calculating the configuration of stiffening beams under multi-node forces was constructed.Furthermore,according to the configuration of the rigid supported continuous beam,an optimization objective function for each suspension point of the stiff girder was established.Finally,based on the nonlinear equations of the mechanical models of the cable system and the stiffening beam system,the mechanical parameterization solution of each member in the bridge state based on the rigid supported continuous beam was realized.The derived analytical algorithm was compared with the research results of FEM.The results show that because of the closure condition of the calculation process,the calculation results of the analytical algorithm are in good agreement with the results of the finite element model.The difference rate of calculation of the key parameters,the suspension cable force and the main cable shape are controlled within 0.1%,and the difference rate of the maximum bending moment of the stiff girder is approximately-0.34%.The derived analytical algorithm is a refined and reasonable closure method of the bridged state,which can be used as a reliable method for the design and calculation of the rational completed state of suspension bridges.11 figs,26 refs.