Angular displacement strain monitoring identification method for defective cable and concentrated loads

Abstract

The invention relates to an angular displacement strain monitoring 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 the angular displacement of a supporting base, the temperature of the cable structure and environment temperature, a mechanical calculation reference model of the cable structure taking the angular displacement of the supporting base, the temperature of the cable structure and the environment temperature into account is obtained, and a value change matrix of unit damage monitored quantities is obtained through calculation on the basis of the model. According to the approximate linear relations between the current numeric vectors of the monitored quantities and the current initial numeric vectors of the monitored quantities, the value change matrix of the monitored unit damage quantities and the current nominal damage vectors of evaluation objects to be solved, the non-inferior solution of the current nominal damage vectors of the evaluation objects is calculated out. Accordingly, the effects of interference factors can be eliminated when the angular displacement of the supporting base and the temperatures change, and the 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 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 in all other conditions. Recognize changes in structural health all other things being equal (only structural temperature and structural health change) Recognize structural (ambient) temperature and structural Changes in the state of health. At present, there is no public and effective method that can simultaneously identify changes in the load on the structure, the temperature of the structure (environment) and the health state of the structure, or in other words, the load on the structure and the temperature of the structure (environment) simultaneously 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, thereby accurately identifying 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 support angular displacement, load change and structural temperature change on the identification results of the cable structure 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 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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