Dynamic characteristics analysis method of flexible hanger based on Wittrick-Williams algorithm

Abstract

As important bearing members of the suspension and arch bridges, flexible slings determine the bearing capacity and durability of bridges. Therefore, it is of great significance to study its dynamic characteristics for the design, operation, and maintenance of suspension and arch bridges. In this paper, first, based on the Euler beam model, the dynamic stiffness method (DSM) is used to systematically derive the solving formula of the frequency equation of the sling considering bending stiffness under any boundary conditions. Combined with the Wittrick-Williams (W-W) algorithm, an accurate method for calculating the vibration modal frequency of the sling is proposed, and a set of fine analysis theory suitable for the dynamic characteristics analysis of the sling is formed. Second, the accuracy of the calculation method and analysis theory is verified by the degradation of model parameters, literature method and finite element modeling. Finally, the comparison with the measured data of Mingzhou Bridge shows that the proposed analysis theory is feasible in practical engineering. The theoretical system provides a reference for further study of the dynamic characteristics of the sling and guides the design and monitoring of the actual engineering sling to a certain extent.