Generalized displacement strain monitoring progressive identification method for defective cable and concentrated loads

Abstract

The invention discloses a generalized displacement strain monitoring progressive identification method for a defective cable and concentrated loads. On the basis of strain monitoring, whether a mechanical calculation reference model of a cable structure needs to be updated or not is determined by monitoring generalized displacement of a supporting seat, temperature of the cable structure and environment temperature, a mechanical calculation reference model of the cable structure taking the generalized displacement of the supporting seat, the temperature of the cable structure and the environment temperature into consideration is obtained, and on the basis of the model, a numerical value changing matrix of unit damage monitored quantities is obtained through calculation. According to the approximate linear relation between current numeric vectors of monitored quantities, current initial numeric vectors of the monitored quantities, the numerical value changing matrix of the unit damage monitored quantities, and current nominal damage vectors of evaluated objects to be solved, the non-inferior solution of the current nominal damage vectors of the evaluated objects to be solved is calculated, accordingly, influences of interference factors can be eliminated when the generalized displacement of the supporting seat exists and the temperature changes, and variable quantities of the concentrated loads and the defective cable can be identified.

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. The damage and slack of supporting cables is a major threat to the safety of cable structures. In this method, damaged cables and slack ca...

AI Technical Summary

Problems solved by technology

[0005] When the support has a generalized 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 in all other conditions. Recognizes changes in structural health all other things being equal (only structural temperature and structural health change) Recognizes structural (ambient) temperature and structure Changes in the health state, there is currently no public and effective method that can simultaneously identify changes in the structural load, structural (environment) temperature, and structural health state, or in other words, the load on the structure and the structural (environment) temperature at the same time When changing, there is no effective method to identify changes in the structural health status, and the load on the structure and the structure (environment) temperature often change, so how to eliminate the load when the load on the structure and the structure (environment) temperature change Changes and structural temperature changes on the health status identification results of cable structures, so as to accurately identify the changes in the health status of the structure, is an urgent problem to be solved at present. This method discloses a method. When the support has a generalized displacement, When the concentrated load borne by the cable structure and the structural (environmental) temperature change, the influence of the generalized displacement of the support, load change and structural temperature change on the identification results of the cable structure's health status can be eliminated, and the problem cable can be identified based on the monitoring of the monitored quantity. It is of great value to the safety of the cable structure

[0006] Similarly, in the currently disclosed methods, there is no method that can eliminate the influence of the generalized displacement of the support, the temperature change of the structure, and the health state of the support cable, so as to realize the correct identification of the change degree of the concentrated load. For the structure, the load It is also very important to identify changes

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