Vulnerability Assessment of Steel Structures in District 12 of Mashhad City and Prioritizing the Welding Defects Using the Analytic Hierarchy Process

Recently, steel structures have been accounted for a large percentage of the buildings due to their advantages such as higher execution speed and easier construction. In steel structures, welded joints are commonly used and their quality plays a key role in stability of buildings under applied loads. Hence, to increase resiliency of welded steel structures against natural hazards, welded joints quality should be improved. In this article, a statistical study was done on welding defects of different connections in 50 welded steel buildings that were being constructed in district 12 (Mashhad, Iran). The reasons for selecting this district were high rates of construction and high potential of hazards. Actually, initial information about joints importance and weld defects were collected by distributed questionnaires among building designer engineers and weld inspectors. In this paper, we used the Expert Choice software that works according to Analytic Hierarchy Process (AHP) to prioritize weld defects in different connections of the buildings and define management solutions to improve them. The priority results revealed that in the non-rigid connections crater, slag inclusion and spatter are more critical whereas in the rigid connections Lack of Penetration (LoP) and Lack of Fusion (LoF) are more critical than the other welding defects in steel building structures.