Magnetic Signal Characteristics in Critical Yield State of Steel Box Girder Based on Metal Magnetic Memory Inspection

Metal magnetic memory testing (MMMT) is a nondestructive technique that can detect early signs of damage in components. Many scholars have studied the effect uniaxial stress on self-magnetic-leakage field (SMLF)’s strength. Nevertheless, there still insufficient research combined action bending and shear. We law distribution signal, ?HSF(y), at different parts steel box girder quantitative relationship between characteristic parameters external load. The results showed MMMT could accurately concentration zone (SCZ) predict final buckling girders. It be judged corresponding had entered elastic-plastic working stage by reverse change ?HSF(y)-F |HSF(y)|a -F curve trends, this feature used as an warning sign before was deformed or destroyed. fitted |HSF(y)|ave linear expression signal shear capacity. All evaluation methods were expected to provide basis for effectively evaluating state girders with method.