Dr. Zuheir Barsoum is Professor of Lightweight Structures at the Department of Engineering Mechanics, KTH Royal Institute of Technology, Stockholm, Sweden. He currently holds a yearly endowment trough SSAB (Swedish Steel Company). His research interests include fatigue and fracture of engineering materials and structures, structural integrity, joining and welding of lightweight metals and computational weld mechanics. He is currently supervising 5 PhD students. He has authored and co-authored more than 200 articles in international journals and conferences. Professor Barsoum is also an expert member and chairperson within IIW (International Institute of Welding). He has authored and co-authored books on IIW design recommendations. Professor Barsoum have received international awards (Granjon Award 2010, Gedik Award 2020) for his contribution to the research field in Design and Structural Integrity. Professor Barsoum have also been very active in commercializing research, including as co-founder of the company Winteria® (www.winteria.se) which develops and sells digitized systems for quality assurance of welding and other manufacturing processes. Professor Barsoum is a member of the Fatigue Design Scientific committee members.
Abstract
In 2016, the International Institute of Welding (IIW) published a recommendation/guideline for HFMI treatment of welded structures including proper treatment procedures, quality control and amount fatigue strength improvement that can be claimed for steel grades 235 – 960 MPa in yield strength, where up to 8 fatigue strength (FAT) improvement can be achieved for High Strength Steel welds. Post weld treatment with HFMI techniques have shown outstanding fatigue life improvement for welded structures and similar recommendations as those in IIW are finding their way into other international standards, e.g. the Eurocodes.
Recently, HFMI techniques have been used in several research projects for life extension of welded steel bridge details, e.g. in Sweden and Japan, with successful results and a clear rehabilitation. The studies within these research programs have focused on; implementation of digitalized weld quality assurance for determining the weld quality pre-and post-weld improvement, development of framework for NDT and DT in order to determine crack size for pre-fatigued welded details to determine the benefits of life extension with HFMI techniques, development of finite element framework for simulation of HFMI process, damage tolerance and fracture mechanical analysis for evaluating experimental results. Results from these research programs give recommendations for acceptable crack size prior life extension using HFMI techniques where IIW recommendations also can be applied for pre-fatigued details.
The current study will give an overview of these research activities and preliminary results with regards to life extension of welded steel details using HFMI techniques.
