Suspender damage identification method for half-through and through arch bridges

Abstract

The invention discloses a suspender damage identification method for half-through and through arch bridges, and the method comprises the following steps: when n suspenders are damaged, selecting n+2 nodes; and by using one of the n+2 nodes as a basic point and the other n+1 nodes as measuring points, constructing n+1 damage identification equations in accordance with the changes of the vertical displacement differences between each measuring point and the basic point before and after the suspenders are damaged, wherein when all the damage identification equations are tenable, epsilon i is thedamage value of the ith suspender, and the damage identification equation is shown in the specification, wherein ({X}j-{X}1) is the vertical displacement difference between the measuring point and the basic point after the suspender is damaged, ({X0}j-{X0}1) is the vertical displacement difference between the measuring point and the basic point before the suspender is damaged, the specification is the first-order perturbation of a suspender system finite element stiffness matrix caused by the damage to the ith suspender after order expansion is defined in the specification, and an inverse matrix of a bridge finite element reference model stiffness matrix under the initial conditions is defined in the specification. By identifying medium and small damages to the suspenders based on the changes of the vertical displacement differences among the nodes, the method disclosed by the invention is practical and ensures higher precision.

Description

technical field [0001] The invention relates to the technical field of damage detection of suspenders of intermediate and under-connected arch bridges, in particular to a damage identification method for suspenders of intermediate and under-connected arch bridges. Background technique [0002] Suspenders are the main force-transmitting components of mid- and under-through arch bridges. During bridge operation, due to the influence of various factors, the suspenders are prone to damage such as steel wire breakage, corrosion, or anchorage failure. Since the suspenders can only bear tension, when the suspenders are damaged, the stress state of the bridge will change, and even endanger the safety of the bridge in severe cases. Therefore, identifying the damage degree of the suspenders is of great significance to ensure the safety of the bridge. . [0003] In recent years, domestic and foreign scholars have conducted research on the damage identification of suspenders. In the e...

AI Technical Summary

Problems solved by technology

At present, the test of boom tension mainly adopts the vibration measurement method, and the boom tension is calculated by testing the lateral vibration frequency of the boom. When calculating the boom tension from the frequency, when parameters such as the stiffness, density and support conditions of the boom cannot be accurately considered, There may be a large error in the tension calculation of the boom, especially for short booms, the error is larger

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