Acoustic Emission Characteristics and Damage Evolution Model of Steel Strands in Tensile Test

Abstract

Conventional non-destructive methods cannot dynamically monitor the steel strands damage evolution process, so acoustic emission technique was proposed to monitor the damage. Experiments on acoustic emission characteristics of full-regime steel strands tensile failure were carried out. Acoustic emission characteristic parameters of steel strand damage were obtained. The test results show that the acoustic emission characteristic parameter is not apparent before fracture, the acoustic emission signal increases rapidly when approaching critical fracture point and appears a big burst signal nearby yield point. According to the correlation figure of acoustic emission accumulative energy, damage characteristic parameter of steel strand can be expressed through acoustic emission accumulative energy, the damage evolution process and law can be dynamically analyzed and broken strand numbers and time are very easily judged. Based on the monitoring data, the relationship between acoustic emission parameter and damage variables was derived. The steel strand tensile damage evolution equation was defined with acoustic emission accumulative energy relative change, the equation can be expressed using Weibull cumulative distribution function, and its rightness and rationality were verified through experiments.