Investigation of the effect of rigid connection type on the nonlinear behavior and over-strength factor of steel special moment frames

Document Type : Technical note

Author

Department of Civil engineering, Kerman Branch, Islamic Azad University, Kerman, Iran

Abstract

After poor performance and brittle fracture of moment connections in the 1994 earthquake in Northridge, researchers proposed new connections to improve the behavior of steel moment frames. Generally, these modified connections can be classified into two main categories: reduced beam section (RBS) and other than RBS connections such as bolted flange plate, bolted unstiffened and stiffened extended end-plate moment, and welded unreinforced flange-welded web moment connections. In this study the behavior of special steel moment frames using each of these two types of connections was investigated. For this purpose, several steel moment frames made up of these two types of connections were analyzed using Opensees software through nonlinear static procedure. For modeling, the behavior of connections was modeled using Bilin material. Then, using FEMAP696, the seismic parameters of all moment frames were determined and compared. Results indicated that the moment frames of RBS connections have higher seismic performance than the other moment frames. Furthermore, based on the numerical results, regardless of the connection type, it seems that 3 is not an appropriate value for the over-strength factor. Based on these numerical results, values equal to 4 and 5 can be proposed for the over-strength factor for moment frames of RBS and other than RBS connections respectively.

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[1] Gates, W.E. and M. Morden. (1995). Lessons from inspection, evaluation, repair and construction of welded steel moment frames following the Northridge Earthquake. Surveys and Assessment of Damage to Buildings Affected by the Northridge Earthquake of January 17, 1994 SAC 95, 6.
[2] Miller, D.K. (1998). Lessons learned from the Northridge earthquake. Engineering Structures, 20(4), 249-260.
[3] Venture, S.J. (1996). Experimental investigations of beam-column subassemblages. SAC-96-01, Parts I and II.
[4] Kim, T., et al. (2000) Steel Moment-Resisting Connections Reinforced with Cover and Flange Plates. SAC Joint Venture, Report SAC/BD-00/27.
[5] Kim, T., et al. (2000). Cover-plate and flange-plate reinforced steel moment-resisting connections. : Pacific Earthquake Engineering Research Center, College of Engineering, University of California, Berkeley.
[6] Hedayat, A.A., Saffari H. and Jazebi E. (2016). Investigation of the effective parameters on the strength and ductility of the welded flange plate connections. Asian Journal of Civil Engineering (BHRC). 17(1), 15-42.
[7] Hedayat, A.A., et al. (2018). Flexural strength prediction of welded flange plate connections based on slenderness ratios of beam elements using ANN. Advances in Civil Engineering. In Press.
[8] Chi, B., Uang, C.-M., Chen A. (2006). Seismic rehabilitation of pre-Northridge steel moment connections: A case study. Journal of Constructional Steel Research, 62(8), 783-792.
[9] Popov, E.P. and Tsai, K. (1989). Performance of large seismic steel moment connections under cyclic loads. Engineering Journal, 26, 2.
[10] Chen, C.-C., Lee, J.-M. and Lin, M.-C. (2003). Behaviour of steel moment connections with a single flange rib. Engineering structures, 25(11), 1419-1428.
[11] Chen, C.-C., Lin, C.-C. and Tsai, C.-L. (1889). Evaluation of reinforced connections between steel beams and box columns. Engineering structures, 26(13), 1889-1904.
[12] Popov, E.P., Yang, T.-S. and Chang, S.-P. (1998). Design of steel MRF connections before and after 1994 Northridge earthquake. Engineering Structures, 20(12), 1030-1038.
[13] Hedayat, A.A. and Celikag, M. (2009).  Post-Northridge connection with modified beam end configuration to enhance strength and ductility. Journal of Constructional Steel Research, 65(7), 1413-1430.
[14] Hedayat, A.A., Saffari, H. and Mousavi, M. (2013). Behaviour of Steel Reduced Beam Web (RBW) Connections with Arch-Shape Cut. Advances in Structural Engineering, 16(10), 1645-1662.
[15] Hedayat, A.A., Saffari, H. and Amid, H. (2016). Ductility of post-Northridge connections with Angelina beams. Proceedings of the Institution of Civil Engineers-Structures and Buildings, 169(SB3), 184-209.
[16] Saffari, H., Hedayat, A. and Nejad, M.P. (2013).  Post-Northridge connections with slit dampers to enhance strength and ductility. Journal of Constructional Steel Research, 80, 138-152.
[17] Oh, S.-H., Kim, Y.-J. and Ryu H.-S. (2009). Seismic performance of steel structures with slit dampers. Engineering structures, 31(9), 1997-2008.
[18] Houghton, D.L. (1998). The SidePlate T M Moment Connection System: A Design Breakthrough Eliminating Recognised Vulnerabilities in Steel Moment-Resisting Frame Connections. Journal of Constructional Steel Research, 1(46), 260-261.
[19] Engelhardt, M. and Sabol, T.A. (1994). Testing of welded steel moment connections in response to the Northridge earthquake. Northridge steel update, 1.
[20] American Institute of Steel Construction, (2016). Prequalified Connections for Special and Intermediate Steel Moment Frames for Seismic Applications. Chicago: ANSI/AISC 358-16.
[21] American Society of Civil Engineers, (2016). Minimum Design Loads and Associated Criteria for Buildings and other structures. ASCE/SEI-7-16, Vol. 7.
[22] Le-Trung, K., et al. (2010). Seismic demand evaluation of steel MRF buildings with simple and detailed connection models. International Journal of Steel Structures, 10(1), 15-34.
[23] Zareian, F., Lignos, D.  and Krawinkler, H. (2010). Evaluation of seismic collapse performance of steel special moment resisting frames using FEMA P695 (ATC-63) methodology. In Structures Congress.
[24] Federal Emergency Management Agency, (2009). Quantification of Building Seismic Performance Factors. FEMA-P695.
[25] Lignos, D., Krawinkler, H. and Whittaker, A. (2011). Prediction and validation of sidesway collapse of two scale models of a 4‐story steel moment frame. Earthquake Engineering & Structural Dynamics, 40(7), 807-825.
[26] Izadinia, M., Rahgozar, M.A. and Mohammadrezaei O. (2012). Response modification factor for steel moment-resisting frames by different pushover analysis methods. Journal of Constructional Steel Research, 79, 83-90.
[27] SeismoSoft, (2004). A computer program for static and dynamic nonlinear analysis of framed structures. [Online] Available at: http://www.seismosoft.com.
[28] Elkady, A. and Lignos, D.G. (2014). Effect of gravity framing on the overstrength and collapse capacity of steel frame buildings with perimeter special moment frames. Earthquake Engineering & Structural Dynamics, 44(8), 1289-1307.
[29] NIST and N.C. Joint, (2010). Evaluation of the FEMA P-695 Methodology for Quantification of Building Seismic Performance Factors. Gaithersburg: US Department of Commerce, Engineering Laboratory, National Institute of Standards and Technology, 20899-8600.
[30] Mckenna, F.T. (1997). Object-oriented finite element programming: frameworks for analysis, algorithms and parallel computing. University of California, Berkeley.
[31] American Society of Civil Engineers, (2010). Minimum design loads for buildings and other structures. American Society of Civil Engineers Standard.
[32] Lignos, D. (2012). Sidesway collapse of deteriorating structural systems under seismic excitations. Stanford university.
[33] Gupta, A. and Krawinkler, H. (1998). Seismic demands for the performance evaluation of steel moment resisting frame structures. Stanford University.
[34] American Institute of Steel Construction, (2010). Seismic Provisions for Structural Steel Buildings. Chicago, AISC 341-10.
[35] American Institute of Steel Construction, (2010). Specification for Structural Steel Buildings. Chicago-Illinois, ANSI/AISC 360-10.
[36] Federal Emergency Management Agency, (2009). Effects of Strength and Stiffness Degradation on Seismic Response. FEMA-P440A.