Rapid analysis method for dynamic characteristics of three-span self-anchored suspension bridge

Abstract

The invention discloses a rapid fine analysis method for dynamic characteristics of a three-span self-anchored suspension bridge, and the method comprises the steps: firstly giving a fine modeling method which can consider the flexural rigidity of a main cable and the elastic support influence of a main tower and a suspension rod, and respectively establishing motion differential equations of a mid-span main cable, a side-span main cable and a stiffening beam on the basis; solving the equation according to a dynamic stiffness method to obtain a unit dynamic stiffness matrix of the main cable and the stiffening girder, and superposing contribution of each unit to obtain a closed-form suspension bridge overall dynamic stiffness matrix and a frequency equation; then, based on a numerical iterative algorithm, realizing accurate solving of the frequency equation, and obtaining modal frequencies and vibration modes of all orders of the system. The method is simple in process, and all intermediate variables are given in a closed form, so that compared with an existing solution, the method has higher calculation precision and efficiency. The established self-anchored suspension bridge model is closer to the actual structure, the solving process is simple, the precision is high, and the efficiency is high.

Description

technical field [0001] The invention belongs to the field of bridge engineering, and relates to a method for analyzing the dynamic characteristics of a three-span self-anchored suspension bridge, and is especially suitable for fast analysis of the natural frequency of the suspension bridge. Background technique [0002] In recent years, self-anchored suspension bridges have become more and more popular among urban bridges due to their beautiful aesthetic shape and flexibility in site selection. Different from the ground-anchored suspension bridge, the self-anchored suspension bridge does not require a large anchorage, and its main cable is directly anchored at both ends of the main girder, thus greatly reducing the geological requirements of the bridge site, so it has gradually become a small and medium-span city. A competitive program of bridges. [0003] The dynamic characteristic analysis of suspension bridge is the basis of seismic design, aerodynamic stability analysis...

AI Technical Summary

Problems solved by technology

The former has a fast calculation speed and is mostly used in the preliminary design and rapid analysis of structures. However, due to the use of approximate displacement functions, the calculation accuracy is limited and it is difficult to use in the fine analysis of structures; the latter has strong applicability, although it can be used It is suitable for the overall and local analysis of complex structures, but its calculation accuracy and solution efficiency are a pair of contradictions, and it is difficult to apply to batch parameter analysis of large structures

Images