The Efficiency of Reduced Beam Section Connections for Reducing Residual Drifts in Moment Resisting Frames

Kamyar Kildashti, Rasoul Mirghaderi, Iradje Mahmoudzadeh Kani

School of Civil Engineering, University of Tehran, Tehran, Iran.

DOI: 10.4236/ojce.2012.22011                

Abstract

In most framed structures anticipated deformations in accordance with current codes fall into acceptable limit states, whereas they go through substantial residual deformations in the aftermath of severe ground motions. These structures seem unsafe to occupants since static imminent instability in the immediate post-earthquake may be occurred. Moreover, rehabilitation costs of extensive residual deformations are not usually reasonable. Apparently, there is a lack of detailed knowledge related to reducing residual drift techniques when code-based seismic design is considered. In this paper, reduced beam section connections as a positive approach are taken action to mitigate the huge amount of residual drifts which are greatly amplified by P-Δ effects. To demonstrate the efficacy of RBS, a sixteen-story moment resisting frame is analyzed based on a suite of 8 single-component near field records which have been scaled according to the code provisions. The results are then processed to assess the effects of RBS detailing on drift profile, maximum drift, and residual drift. Besides, a special emphasis is given to estimate overall trend towards drift accumulation in each story in the presence of RBS assembly. A main conclusion is that using this connection predominantly alleviates the adverse effects of P-Δ on amplifying residual drifts.

Keywords

Residual Deformations; Reduced Beam Section Connection; P-Δ Effects

Conflicts of Interest

The authors declare no conflicts of interest.

References

[1]	D. Pettinga, C. Christopoulos, S. Pampanin and M. J. N. Priestley, “Effectiveness of Simple Approaches in Mitigating Residual Deformations in Buildings,” Earthquake Engineering and Structural Dynamics, Vol. 36, No. 12, 2007, pp. 1763-1783. doi:10.1002/eqe.717
[2]	K. Kiggins and C. M. Uang, “Reducing Residual Drift of Buckling-Restrained Braced Frames as a Dual System,” Engineering Structures, Vol. 28, No. 11, 2006, pp. 1525- 1532. doi:10.1016/j.engstruct.2005.10.023
[3]	G. A. MacRae and K. Kawashima, “Post-Earthquake Residual Displacements of Bilinear Oscillators,” Earthquake Engineering and Structural Dynamics, Vol. 26, No. 7, 1997, pp. 701-716. doi:10.1002/(SICI)1096-9845(199707)26:7<701::AID-EQE671>3.0.CO;2-I
[4]	C. Christopoulos, A. Filiatrault, C. M. Uang and B. Filz, “Post-Tensioned Energy Dissipating Connections for Moment-Resisting Steel Frames,” Journal of Structural Engineering, Vol. 128, No. 9, 2002, pp. 1111-1120. doi:10.1061/(ASCE)0733-9445(2002)128:9(1111)
[5]	J. Iyama, C. Y. Seo, J. M. Ricles and R. Sause, “Self- Centering MRFs with Bottom Flange Friction Devices under Earthquake Loading,” Journal of Constructional Steel Research, Vol. 65, No. 2, 2009, pp. 314-325. doi:10.1016/j.jcsr.2008.02.018
[6]	C. C. Chou and Y. J. Lai, “Post-Tensioned Self-Centering Moment Connections with Beam Bottom Flange Dissipaters,” Journal of Constructional Steel Research, Vol. 65, No. 10-11, 2009, pp. 1931-1941. doi:10.1016/j.jcsr.2009.06.002
[7]	S. R. Uma, S. Pampanin and C. Christopoulos, “A Probabilistic Framework for Performance-Based Seismic Assessment of Structures Considering Residual Deformations,” Proceedings of the 1st ECEES, Geneva, 3-6 September 2006, 731.
[8]	J. Ruiz-Garcia and E. Miranda, “Probabilistic Estimation of Residual Drift Demands for Seismic Assessment of Multi-Story Framed Buildings,” Engineering Structures, Vol. 32, No. 1, 2010, pp. 11-20. doi:10.1016/j.engstruct.2009.08.010
[9]	J. Ruiz-Garcia and E. Miranda, “Evaluation of Residual Drift Demands in Regular Multi-Story Frames for Performance-Based Seismic Assessment,” Earthquake Engineering and Structural Dynamics, Vol. 35, No. 13, 2006, pp. 1609-1629. doi:10.1002/eqe.593
[10]	J. Ruiz-Garcia and E. Miranda, “Residual Displacement Ratios for Assessment of Existing Structures,” Earthquake Engineering and Structural Dynamics, Vol. 35, No. 3, 2006, pp. 315-336. doi:10.1002/eqe.523
[11]	C. Christopoulos, S. Pampanin and M. J. N. Priestley, “Performance-Based Seismic Response of Frame Structures Including Residual Deformations. Part I: Single-Degree of Freedom Systems,” Journal of Earthquake Engineering, Vol. 7, No. 1, 2003, pp. 97-118. doi:10.1080/13632460309350443
[12]	C. Christopoulos, S. Pampanin and M. J. N. Priestley, “Performance-Based Seismic Response of Frame Structures Including Residual Deformations. Part II: MultiDegree of Freedom Systems,” Journal of Earthquake Engineering, Vol. 7, No. 1, 2003, pp. 119-147. doi:10.1080/13632460309350443
[13]	J. Shen, T. Kitjasateanphun and W. Srivanich, “Seismic Performance of Steel Moment Frames with Reduced Beam Sections,” Engineering Structures, Vol. 22, No. 8. 2000, pp. 968-983. doi:10.1016/S0141-0296(99)00048-6
[14]	J. Jin and S. El-Tawil, “Seismic Performance of Steel Frames with Reduced Beam Section Connections,” Journal of Constructional Steel Research, Vol. 61, No. 4, 2005, pp. 453-471. doi:10.1016/j.jcsr.2004.10.006
[15]	K. Kildashti and R. Mirghaderi, “Assessment of Seismic Behavior of SMRFs with RBS Connections by Means of Mixed-Based State-Space Approach,” The Structural Design of Tall and Special Buildings, Vol. 18, No. 5, 2008, pp. 485-505. doi:10.1002/tal.450
[16]	S. J. Chen, C. H. Yeh and J. M. Chu, “Ductile Steel Beam-to-Column Connections for Seismic Resistance,” Journal of Structural Engineering, Vol. 122, No. 11, 1996, pp. 1292-1299. doi:10.1061/(ASCE)0733-9445(1996)122:11(1292)
[17]	A. Plumier, “The Dog-Bone: Back to the Future,” Engineering Journal, Vol. 34, No. 2, 1997, pp. 61-67.
[18]	M. Bruneau, C. M. Uang and A. Whittaker, “Ductile Design of Steel Structures,” McGraw-Hill, New York, 1998.
[19]	S. L. Jones, G. T. Fry and M. D. Engelhardt, “Experimental Evaluation of Cyclically Loaded Reduced Beam Section Moment Connections,” Journal of Structural Engineering, Vol. 128, No. 4, 2002, pp. 441-451. doi:10.1061/(ASCE)0733-9445(2002)128:4(441)
[20]	ASCE-041, “Seismic Rehabilitation of Existing Buildings,” American Society of Civil Engineers, Reston, 2006.
[21]	ASCE 7, “Minimum Design Loads for Buildings and Other Structures,” American Society of Civil Engineers, Reston, 2006.
[22]	V. K. Simeonov, M. V. Sivaselvan and A. M. Reinhorn, “Nonlinear Analysis of Structural Frame Systems by the State Space Approach,” Computer-Aided Civil and Infrastructure Engineering, Vol. 15, No. 2, 2000, pp. 76-89. doi:10.1111/0885-9507.00174
[23]	M. V. Sivaselvan and A. M. Reinhorn, “Collapse Analysis: Large Inelastic Deformations Analysis of Planar Frames,” Journal of Structural Engineering, Vol. 128, No. 12, 2002, pp. 1575-1583. doi:10.1061/(ASCE)0733-9445(2002)128:12(1575)
[24]	R. Frish-Fay, “Flexible Bars,” Butterworth, London, 1962.
[25]	S. L. Chan, “Geometric and Material Non-Linear Analysis of Beam-Columns and Frames Using the Minimum Residual Displacement Method,” International Journal for Numerical Methods in Engineering, Vol. 26, No. 12, 1988, pp. 2657-2669. doi:10.1002/nme.1620261206
[26]	M. A. Crisfield, “A Consistent Co-Rotational Formulation for Nonlinear, Three Dimensional Beam Elements,” Computer Methods in Applied Mechanics and engineering, Vol. 81, No. 2, 1990, pp. 131-150. doi:10.1016/0045-7825(90)90106-V
[27]	M. Schulz and F. C. Filippou, “Non-Linear Spatial Timoshenko Beam Element with Curvature Interpolation,” International Journal for Numerical Methods in Engineering, Vol. 50, No. 4, 2001, pp. 761-785. doi:10.1002/1097-0207(20010210)50:4<761::AID-NME50>3.0.CO;2-2