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


1 Department of Civil Engineering, Khavaran Institute of Higher Education, Mashhad, Iran

2 Department of Civil Engineering and environment, Amir Kabir University, Tehran, Iran

3 Department of Civil Engineering and environment,, Texas State University, Texas, USA


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.


1. Song, J. and Ellingwood, B.R., "Seismic reliability of special moment steel frames with welded connections: Ii", Journal of Structural Engineering,  Vol. 125, No. 4, (1999), 372-384.
2. Roeder, C.W., "Connection performance for seismic design of steel moment frames", Journal of Structural Engineering,  Vol. 128, No. 4, (2002), 517-525.
3. Liao, T.W., "Classification of welding flaw types with fuzzy expert systems", Expert Systems with Applications,  Vol. 25, No. 1, (2003), 101-111.
4. Kiral, B.G. and Erim, S., "Prediction of fracture behavior of steel beam-to-column connections with weld defect using the sintap", Engineering Structures,  Vol. 27, No. 5, (2005), 760-768.
5. Cerit, M., Kokumer, O. and Genel, K., "Stress concentration effects of undercut defect and reinforcement metal in butt welded joint", Engineering Failure Analysis,  Vol. 17, No. 2, (2010), 571-578.
6. Zhang, J. and Dong, P., "Residual stresses in welded moment frames and implications for structural performance", Journal of Structural Engineering,  Vol. 126, No. 3, (2000), 306-315.
7. Mahin, S.A., "Lessons from damage to steel buildings during the northridge earthquake", Engineering Structures,  Vol. 20, No. 4-6, (1998), 261-270.
8. Dubina, D. and Stratan, A., "Behaviour of welded connections of moment resisting frames beam-to-column joints", Engineering Structures,  Vol. 24, No. 11, (2002), 1431-1440.
9. Finch, D. and Burdekin, F., "Effects of welding residual stresses on significance of defects in various types of welded joint", Engineering Fracture Mechanics,  Vol. 41, No. 5, (1992), 721-735.
10. Azuma, K., Kurobane, Y. and Makino, Y., "Cyclic testing of beam-to-column connections with weld defects and assessment of safety of numerically modeled connections from brittle fracture", Engineering Structures,  Vol. 22, No. 12, (2000), 1596-1608.
11. Rafiee, R., Mahiny, A.S., Khorasani, N., Darvishsefat, A.A. and Danekar, A., "Simulating urban growth in mashad city, iran through the sleuth model (ugm)", Cities,  Vol. 26, No. 1, (2009), 19-26.
12. Motagh, M., Djamour, Y., Walter, T.R., Wetzel, H.-U., Zschau, J. and Arabi, S., "Land subsidence in mashhad valley, northeast iran: Results from insar, levelling and gps", Geophysical Journal International,  Vol. 168, No. 2, (2007), 518-526.
13. Dehghani, M., Zoej, M.J.V., Saatchi, S., Biggs, J., Parsons, B. and Wright, T., "Radar interferometry time series analysis of mashhad subsidence", Journal of the Indian Society of Remote Sensing,  Vol. 37, No. 1, (2009), 147-156.
14. Anand, R. and Kumar, P., "Flaw detection in radiographic weld images using morphological approach", NDT & E International,  Vol. 39, No. 1, (2006), 29-33.
15. Barlett, J.E., Kotrlik, J.W. and Higgins, C.C., "Organizational research: Determining appropriate sample size in survey research", Information Technology, Learning, and Performance Journal,  Vol. 19, No. 1, (2001), 43-50.
16. Ishizaka, A. and Labib, A., "Analytic hierarchy process and expert choice: Benefits and limitations", Or Insight,  Vol. 22, No. 4, (2009), 201-220.
17. Saaty, T.L., "Decision making with the analytic hierarchy process", International journal of services sciences,  Vol. 1, No. 1, (2008), 83-98.
18. Al-Harbi, K.M.A.-S., "Application of the ahp in project management", International Journal of Project Management,  Vol. 19, No. 1, (2001), 19-27.
19. Bitarafan, M., Zolfani, S.H., Arefi, S.L. and Zavadskas, E., "Evaluating the construction methods of cold-formed steel structures in reconstructing the areas damaged in natural crises, using the methods ahp and copras-g", Archives of Civil and Mechanical Engineering,  Vol. 12, No. 3, (2012), 360-367.