Broken Wire Identification in Bridge Cables Based on Magnetic Flux Leakage Examination

Abstract:

A damageidentification method based on effective shorttime crosscorrelation (STCC) was proposed to identify wire breakage, in the case of low signal-to-noise (SNR) ratio with the magnetic flux leakage (MFL) detection of bridge cables. The corresponding signal fragment from repeated tests of the cable was extracted for effective STCC analysis. The effective STCC was renormalized to combine with the characteristics of short-time energy. Then, the double threshold method was used to identify the broken wire damage. A full-scale cable model with various kinds of wire breakage was made for MFL examination, and the experimental results were used to verify the proposed method. The results show that the proposed method improves the damagerecognition accuracy by about 15.7%~16.9% compared with the existing methods, and obtains high identification accuracy even with low SNR ratio.

Key words:bridge cable; broken wire; magnetic flux leakage (MFL) examination; effective short-time cross correlation (STCC); model experiment