The Effects of Using Easy-Going Steel Knee Element on Seismic Behavior of CKBF

Document Type : Research

Authors

1 M.Sc. in Structural Engineering, K. N. Toosi University of Technology, Department of Civil Engineering, Tehran, Iran.

2 Associate Professor, K. N. Toosi University of Technology, Department of Civil Engineering, Tehran, Iran.

Abstract

A proper composition of stiffness and ductility parameters is required to obtain a resistant and economic structure. Accordingly, Chevron Knee Braced Frame (CKBF) seems appropriate due to its proper seismic performance. The advantage of this system comes to having the capability of rapid and cheap replacement of chevron knee elements after an earthquake occurs. In this research, response modification factor and over-strength factor are determined for CKBF in two statuses of chevron V bracing and chevron inverted V bracing. The effect of using Easy-Going Steel (EGS) on the knee is also studied in the 3,6,9 and 12 story frames. In addition, the methods used for this purpose are nonlinear static analysis, linear dynamic analysis and Incremental Dynamic Analysis (IDA). IDAs have been conducted on 17 records of important universal earthquakes using Opensees software.

Keywords


1. Roeder, C.W., Popov, E.P., (1978). "Eccentrically brace steel frames for earthquakes", Journal of Structural Division, 104 (ST3), 391-412.
2. Aristizabal-Ochoa, J.D., (1986). "Disposable knee bracing: Improvement in seismic design of steel frame", Journal of Structural Engineering, 112(7), 1544-1552. [DOI:10.1061/(ASCE)0733-9445(1986)112:7(1544)]
3. Balendra, T., Sam, M.T. and Liaw, C.Y., (1990). "Diagonal brace with ductile knee anchor for and seismic steel frames", Journal of Earthquake Engineering and Structural Dynamics, 19(6), 847-858. [DOI:10.1002/eqe.4290190606]
4. Balendra, T., Lim, E.L. and Lee, S.L., (1994). "Ductile knee braced frames with shear yielding knee for seismic resistant structures", Engineering Structures, 16(4):263-269. [DOI:10.1016/0141-0296(94)90066-3]
5. Lotfollahi, M. and Mofid, M., (2006). "On the design of new ductile knee bracing", Journal of Constructional Steel Research, 62, 282-294. [DOI:10.1016/j.jcsr.2005.07.004]
6. Jafar Ramaji, I. and Mofid, M., (2012). "On the characteristics and seismic study of Hat Knee Bracing System, in steel structures", Steel and Composite Structures, Journal 13(1), 1-13. [DOI:10.12989/scs.2012.13.1.001]
7. Hsu, H.L., Juang, J.L. and Chou, C.H., (2011). "Experimental evaluation on the seismic performance of steel knee braced frame structures with energy dissipation mechanism", Steel and Composite Structures, An International Journal, Vol. 11(1), 77-91. [DOI:10.12989/scs.2011.11.1.077]
8. Keipour, N., Zafarkhah, E. and Mofid, M., (2012). "Effect of Height of Buildings and Arrangement of Braces on RC Buildings Retrofitted with Steel Knee Braces Based on Incremental Dynamic Analysis (IDA)", The 15th World Conference on Earthquake Engineering, September 24-28, Lisbon, Portugal.
9. Jamalvand, Sed-Y., Alirezaei, M. and Pilevarian, K., (2013). "Nonlinear Behavior and Dissipated Energy of Knee Braced Frames Based on Cyclic Analysis", Journal of Emerging Trends in Engineering and Development, Vol.5, 22-30.
10. Farahi, M. and Mofid, M., (2013). "On the Quantification of Seismic Performance Factors of Chevron-Knee Bracings in Steel Structures", Engineering Structures, 46: 155-164. [DOI:10.1016/j.engstruct.2012.06.026]
11. Sabouri-Ghomi, S., (2004). "Lateral load resisting systems, an innovative idea to application of Easy-Going Steel (EGS)", Angizeh press, Tehran, Iran.
12. Sabouri-Ghomi, S. and Ziaei, M., (2008). "A study on behavior of shear link beam made of easy-going steel in eccentrically braced frames", The 14th World Conference on Earthquake Engineering, October 12-17, Beijing, China.
13. Mofid, M. and Lotfollahi, M., (2006). "On the characteristics of new ductile knee bracing systems", Journal of Constructional Steel Research, 62, 271-281. [DOI:10.1016/j.jcsr.2005.07.005]
14. ASCE/SEI., (2010) "Minimum design loads for buildings and other structures', American Society of Civil Engineering.
15. AISC 360-10 (2010). "Specification for Structural Steel Buildings", American Institute of Steel Construction, Chicago, IL, USA.
16. Asgarian, B. and Shokrgozar, H.R. (2009). "BRBF response modification factor", Journal of Constructional Steel Research, 65, 290-298. [DOI:10.1016/j.jcsr.2008.08.002]
17. Mazzoni, S., McKenna, F., Scott, M.H., Fenves, G.L., and Jeremic B. (2007). "Opensees Command Language Manual".
18. Uang, CM. (1991). "Establishing R (or Rw) and Cd factor for building seismic provision", Journal of Structure Engineering, 117(1), 19-28. [DOI:10.1061/(ASCE)0733-9445(1991)117:1(19)]
19. Mwafy, A.M. and Elnashai A.S. (2002). "Calibration of force reduction factors of RC buildings". Journal of Earthquake Engineering, 6(22), 239-73. [DOI:10.1080/13632460209350416]
20. Vamvatsikos, D. and Cornell, C.A. (2003). "Incremental Dynamic Analysis", Earthquake Engineering and Structural Dynamics, 31(3), 491-514. [DOI:10.1002/eqe.141]