Damaged cable/concentrated load recognition method on basis of angular displacement strain monitoring

Abstract

The invention relates to a damaged cable / concentrated load recognition method on the basis of angular displacement strain monitoring, which is based on strain monitoring. Bracket angular displacement, cable structure temperature and ambient temperature are monitored to determine whether a mechanical calculation reference model of the cable structure needs to be updated, thereby obtaining a mechanical calculation reference model of the cable structure counting in the bracket angular displacement, cable structure temperature and ambient temperature; and the calculation is performed on the basis of the model to obtain unit-damage monitored quantity value change matrix. The noninferior solution of the evaluated object current nominal damage vector is calculated according to the near linear relationship among the monitored quantity current value, monitored quantity current initial value vector, unit-damage monitored quantity value change matrix and unknown evaluated object current nominal damage vector, thereby eliminating the influence of interference factors and recognizing the concentrated load variation and damaged cable in the presence of bracket angular displacement and temperature change.

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

[0005] When the support has an angular 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 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 have an impact on the identification results of the health state of the cable structure, so as to accurately identify changes in the health state of the structure, which is an urgent problem to be solved at present. This method discloses a method. When the support has angular displacement, When the concentrated load borne by the cable structure and the structural (environmental) temperature change, the influence of the bearing angular displacement, load change and structural temperature change on the health status identification of the cable structure can be eliminated, and the damaged cable can be identified based on the monitoring of the monitored quantity. , which is of great value to the safety of the cable structure

[0006] Similarly, in the currently disclosed methods, there has not been a method that can eliminate the influence of support angular displacement, structural temperature change, and support cable health status, so as to realize the correct identification of the degree of concentrated load change. For structures, the load It is also very important to identify changes

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