عنوان مقاله [English]
Acoustic emission is one of the most important technique in None Distructive Test, that is able to evaluate crack growth in steel element of structure and is efficient in order to condition monitoring for deployment on in-service bridge component and these data can be used for schedule planning for maintanance of bridge structure. In line of experiments and empirical research, samples of structural steel (St52) were used as compact tension specimen in axial tensile fatigue test in order to study the crack growth. In this study, application of acoustic emission technique for health monitoring and determination of crack length in components of steel structure which are nuder axial fatigue load are investigated by using experimental test result, for this purpose correlation between acoustic emission parameters such a energy rate, count rate and etc and crack length and fatigue life has been studied. Finally by using the extrcted data from acoustic emission and fatigue test result, and least mean square regression analysis, the constants value for relation between crack length and acoustic emission parameters have been determined.