Damaged cable, concentrated load and support line displacement identification method based on strain monitoring

Abstract

A damaged cable, concentrated load and support line displacement identification method based on strain monitoring is characterized in that based on strain monitoring, a mechanical calculation reference model of cable structure, considering cable structure temperature and environmental temperature, is obtained by monitoring the cable structure temperature and the environmental temperature to determine whether or not the mechanical calculation reference model of cable structure needs to be updated; based on the model, a unit damage monitored numeric change matrix is obtained by calculating; according to approximately linear relation of current numeric vector of monitored value to current initial numeric vector of the monitored value, the unit damage monitored numeric change matrix, and evaluation object current nominal damage vector to be obtained, a non-inferior solution of the evaluation object current nominal damage vector is calculated; accordingly, support line displacement, concentrated load change and a damaged cable are identified in case of temperature changes.

Description

technical field [0001] Cable-stayed bridges, suspension bridges, truss structures and other structures have one thing in common, that is, they have many parts that bear tensile loads, such as cable-stayed cables, main cables, slings, tie rods, etc. , cables, or rods that only bear tensile loads are supporting components. For the sake of convenience, this method expresses this type of structure as The rods under tension or axial compression loads (also known as two-force rods) are collectively referred to as "cable systems" for convenience, and the term "supporting cables" is used in this method to refer to bearing cables, bearing cables and A member that bears axial tension or axial compression load is sometimes referred to as a "cable", so when the word "cable" is used later, it actually refers to a two-force member for a truss structure. During the service process of the structure, the correct identification of the health state of the supporting cables or the cable system i...

AI Technical Summary

Problems solved by technology

[0004] When the support has a linear displacement, some of the currently disclosed technologies and methods can only identify the change of the structure’s load when all other conditions remain unchanged (only the load on the structure changes), and some can only identify the change of the load on the structure under all other conditions. Recognizes changes in structural health when constant (only structural health changes) and some only recognizes structural (environmental) temperature and structural health while all other things are constant (only structural temperature and structural health change) State changes, there is currently no public and effective method that can simultaneously identify changes in structural load, structural (environment) temperature, and structural health status, or in other words, when the load on a structure and the structural (environment) temperature change simultaneously At that time, there is no effective method to identify the change of the structural health status, and the load on the structure and the structural (environmental) temperature are often changed, so how to eliminate the load change when the load on the structure and the structural (environmental) temperature change and the impact of structural temperature changes on the identification results of the health state of the cable structure, so as to accurately identify the change of the health state of the structure is an urgent problem to be solved at present. This method discloses a method that can be used when the support is wired. When the concentrated load on the cable structure and the structural (environmental) temperature change, the influence of the support line displacement, load change and structural temperature change on the identification results of the cable structure health status is eliminated, and the damaged cable is identified based on the monitoring of the monitored quantity. The safety of the cable structure is of great value

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