High-precision cable tension force test method based on model analysis

Abstract

The invention relates to a high-precision cable tension force test method based on model analysis, which comprises the following steps: fixing two or more acceleration sensors on a cable along the cable surface to measure and obtain cable model information; judging the cable model preliminarily, refining the test point arrangement according to a modal identification result, continuously measuring and improving the cable vibration shape, and judging whether a cable modal vibration shape test result forms a complete vibration shape model or not; correcting the sensitivity of the test result of the formed complete vibration shape model, multiplying an identification result by a sensitivity correction coefficient according to the difference of acceleration sensitivities when correcting the sensitivity, obtaining corresponding modal circular frequency omega, and fitting a finally obtained vibration shape curve and obtaining a corresponding vibration shape function, and calculating the actual cable tension force according to the function. Influencing factors controlling the calculation are all obtained by actual measurement, the test error is limited within a certain range, and the calculation result is sure to have extra high reliability.

Description

technical field [0001] The invention relates to the detection of the tension of the cable, in particular to a method for testing the force of the cable with high precision based on modal analysis. Background technique [0002] With the development of society, more and more new structural forms and new materials have entered the social construction. Among them, the cable-containing space structure is widely used in cable-stayed bridges, suspension bridges, arch bridges, mast structures, large In structures such as spanning roofs and glass curtain walls. For cable-bearing bridges, the cable is an important structural component and the main load-bearing member, and the tension measurement of the old and new cables is the main evaluation basis for its reliability and load-bearing state. For the application of cables in building structures, the change of cable force will change the shape and internal force distribution of the overall structure, and may bring catastrophic consequ...

AI Technical Summary

Problems solved by technology

However, the length of cables used in urban bridges and building structures is often short. Not only the stiffness of the cable itself has a great influence on the vibration frequency of the cable itself, but also the boundary forms at both ends of the cable change with the change of the cable force. will change, or the corresponding equivalent calculation cable length will change, if the cable force is still calculated according to the hinge, the result will be unreliable

However, the frequency method itself cannot take these problems into consideration, unless a suitable calculation model is established according to the actual situation to re-deduce the calculation formula of the cable force, so the so-called result correction can only rely on sufficient experience and judgment, or a more reliable detection method

[0005] In addition, new cable-containing spatial structural systems such as cable nets have begun to enter the structure construction, and the influencing factors of cable force testing are becoming more and more complex and diverse, and the previous methods based on ideal models are becoming more and more cramped.

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