Investigation of the effects of Retrofitting the Connection of Steel Beam to Concrete-Filled Steel Tube Column with Bidirectional Bolts by Haunch plates

Document Type : Research Article


1 M.Sc. Structural Engineering, Department of Civil Engineering, College of Engineering, Zanjan Branch, Islamic Azad University, Zanjan, Iran.

2 Assistant Professor, Structural Enginnering, Department of Civil Engineering, Zanjan Branch, Islamic Azad University, Zanjan, Iran.


So far, a lot of research has been done on concrete-filled tubes (CFT) columns and their connections in different countries and several alternatives have been proposed for their connections. However, most of the proposed connections are associated with executive problems and have not been able to create rigid connection conditions. On the other hand, in these connections, the load enters the concrete indirectly and the concrete core does not mobilize well against the applied loads. For steel moment frames that columns are of CFT type, new and suitable methods have been proposed to improve the behavior of their fixed connections. Among them are bidirectional bolted connections in this study; the effect of strengthening this type of connection using haunch plated is surveyed. In these models, the main variables are haunch plates and column plate thickness. The results showed that by examining the formation of the position of the plastic hinge, it could be said that in the model without the haunch plate, plastic hinges and maximum strains are formed almost at the connection and on the face of columns. In most models retrofitted by haunch plates, however, the location of the plastic hinge is in the off-connection area, approximately 20 cm side of the column. It has been seen that the CFT connections retrofitted by haunch plates, energy absorption has increased by 22.62% and the moment capacity bearing has increased by 3%.


Main Subjects

[1] M.Banazadeh, H. Parvini Sani, M. Gholhaki, Decision-making analysis for seismic retrofit based on risk management, Asian Journal of Civil Engineering, 14(5) (2013) 735-746.
[2] H. Parvini Sani, M. Gholhaki, M. Banazadeh, Simplified direct loss measure for seismic isolated steel moment-resisting structures, Journal of Constructional Steel Research 147 (2018) 313–323.
[3] H. Parvini Sani, M. Gholhaki, M. Banazadeh, Seismic performance assessment of isolated low-rise steel structures based on loss estimation, Journal of Performance of Constructed Facilities, 31(4) (2017) 04017028-1:9. 
[4] D.Zhang, J. Zhao, Y.Zhang, Experimental and numerical investigation of concrete-filled double-skin stee l tubular column for steel beam joints, Advances in Materials Science and Engineering, Special issue: Sustainable Building Materials and Technologies 2018, ID:6514025
[5] Gross, J. L., 2001, AISC Design Guide No. 12 Modification of Existing Welded Steel Moment Frame Connections for Seismic Resistance, North American Steel Constrction Conference; 2001.
[6] C.A. Cornell, F. Jalayer, O. Hamburger Ronald, A. Foutch Douglas, Probabilistic basis for 2000 SAC federal emergency management agency steel moment frame guidelines, Journal of Structural Engineering, 128(4) (2002) 526-533.
[7] O. Rezaifar, A. Younesi, Experimental study discussion of the seismic behavior on new types of internal/external stiffeners in rigid beam-to-CFST/HSS column connections, Construction and Building Materials, 136 (2017) 574-589.
[8] J. Beutel, D. Thambiratnam, N. Perera, Cyclic behaviour of concrete filled steel tubular column to steel beam connections, Engineering Structures, 24(1) (2002) 29-38.
[9] L.-Y. Wu, L.-L. Chung, S.-F. Tsai, C.-F. Lu, G.-L. Huang, Seismic behavior of bidirectional bolted connections for CFT columns and H-beams, Engineering Structures, 29(3) (2007) 395-407
[10] L.-Y. Wu, L.-L. Chung, S.-F. Tsai, T.-J. Shen, G.-L. Huang, Seismic behavior of bolted beam-to-column connections for concrete filled steel tube, Journal of Constructional Steel Research, 61(10) (2005) 1387-1410.
[11] J.-F. Wang, L.-H. Han, B. Uy, Behaviour of flush end plate joints to concrete-filled steel tubular columns, Journal of Constructional Steel Research, 65(4) (2009) 925-939.
[12] J. Wang, L. Chen, Experimental investigation of extended end plate joints to concrete-filled steel tubular columns, Journal of Constructional Steel Research, 79 (2012) 56-70.
[13] Y. Qin, Z. Chen, and X. Wang, Experimental investigation of new internal-diaphragm connections to CFT columnsu cyclic loading, Journal of Constructional Steel Research 98 (2014) 35–44.
[14] Y. Yu, Z. Chen, X. Wang, Effect of column flange flexibility on WF-beam to rectangular CFT column connections, Journal of Constructional Steel Research, 106 (2015) 184-197.
[15] Y.-F. Yang, C. Hou, C.-Y. Meng, L.-H. Han, Investigation on square concrete filled double-skin steel tube (CFDST) subjected to local bearing force: Experiments, Thin-Walled Structures, 94 (2015) 394-409.
[16] J. Wang, N. Zhang, S. Guo, Experimental and numerical analysis of blind bolted moment joints to CFTST columns, Thin-Walled Structures, 109 (2016) 185-201.
[17] M. Zeinizadeh Jeddi, N.H. Ramli Sulong, Pull-out performance of a novel anchor blind bolt (tubebolt) for beam to concrete-filled tubular (CFT) column bolted connections, Thin-Walled Structures, 124 (2018) 402–414.
[18] M.M. Ahmadi, S.R. Mirghaderi, Experimental studies on through-plate moment connection for beam to HSS/CFT column, Journal of Constructional Steel Research, 161 (2019) 154-170.
[19] N. Fanaie, H.S. Moghadam, Experimental study of rigid connection of drilled beam to CFT column with external stiffeners, Journal of Constructional Steel Research, 153 (2019) 209-221.
[20] X. Li, T. Zhou, J. Li, X.-B. Kuang, Y.-W. Zhao, Seismic behavior of encased CFT column base connections, Engineering Structures, 182 (2019) 363-378.
[21] G. Zhou, Y. An, D. Li, J. Qu, Analytical model of moment-rotation relation for steel beam to CFST column connections with bidirectional bolts, Engineering Structures ,196 (2019) 109374.
[22] A. Parvari, S.M. Zahrai, S.M. Mirhosseini, E. Zeighami, Numerical and experimental study on the behavior of drilled flange steel beam to CFT column connections, Structures, 28 (2020) 726-740.
[23] X.T. Wang, C.D. Xie, Y. Luo, J.P. Zhang, Experimental and analytical investigation on post-tensioned beam-to-CFST column connection using wedge-shaped devices, Journal of Constructional Steel Research, 169 (2020) 106052.
[24] Y.F. Li, S.H. Chen, K.C. Chang, K.Y. Liu, A constitutive model of concrete confined by steel reinforcements and steel jackets, Canadian Journal of Civil Engineering, 32(1) (2005) 279-288.
[25] L.-H. Han, W. Li, R. Bjorhovde, Developments and advanced applications of concrete-filled steel tubular (CFST) structures: Members, Journal of Constructional Steel Research, 100 (2014) 211-228.
[26] Y. Qin, Z. Chen, Q. Yang, K. Shang, Experimental seismic behavior of through-diaphragm connections to concrete-filled rectangular steel tubular columns, Journal of Constructional Steel Research, 93 (2014) 32-43.