Achievement of Minimum Seismic Damage for Zipper Braced Frames Based on Uniform Deformations Theory

Document Type : Regular Paper


1 Associate Professor, Faculty of Civil Engineering, Babol University of Technology, Babol, Iran

2 Ph.D. Student, Faculty of Civil Engineering, Babol University of Technology, Babol, Iran

3 Assistant Professor, Department of Civil Engineering, University of Mazandaran, Babolsar, Iran


When structures are subjected to strong ground motion excitations, structural elements may be prone to yielding, and consequently experience significant levels of inelastic behavior. The effects of inelastic behavior on the distribution of peak floor loads are not explicitly accounted for in current seismic code procedures. During recent years, many studies have been conducted to develop new design procedures for different types of buildings through proposing improved design lateral load patterns. One of the most important parameters of structural damage in performance-based seismic design is to limit the extent of structural damages (maximum inter-story ductility ratio) in the system and distribute them uniformly along the height of the structures. In this paper, a practical method is developed for optimum seismic design of zipper-braced frames (ZBF) subjected to seismic excitations. More efficient seismic design is obtained by redistributing material from strong to weak parts of a structure until a state of uniform ductility ratio (damage) prevails. By applying the proposed design algorithm on 5, 10 and 15‐storey zipper-braced frames subjected to 10 synthetic seismic excitations, the efficiency of the proposed method is investigated for specific synthetic seismic excitations. The results indicate that, for a constant structural weight, the structures designed according to the proposed optimization algorithm experience up to 50% less global ductility ratio (damage) compared with code-based design structures.


Main Subjects

[1] Green, N.B. (1981). “Earthquake Resistant Building Design and Construction”. Second   Edition, Van Nostrand Reinhold Company, New York.
[2] Hart, G.C. (2000). “Earthquake forces for the lateral force code”. The structural Designof Tall Buildings, Vol. 9, pp. 49-64.
[3] Chopra, A.K. (2001). “Dynamics of structures, Theory and Applications to EarthquakeEngineering”. 2nd Edition, Prentice Hall Inc., London.
[4] Mahin, S.A. (1998). “Lessons from damage to steel buildings during the Northridgeearthquake”. Engineering Structures, Vol. 20, No. 4, pp. 261-270.
[5] Building Seismic Safety Council (BSSC). “National Earthquake Hazard Reduction Program (NEHRP)”. Recommended Provisions for Seismic Regulations for 348 New Buildings and Other Structures-Part 2: Commentary (FEMA450–2), Federal Emergency Management Agency, Washington, D. C, 2003.
[6] IBC (2012). “International Building Code. International Code Council”. Country Club Hills, USA.
[7] UBC (1997). “Structural engineering design provisions. In: Uniform building code”. International conference of building officials, Vol.2.
[8] Park, K., Medina, RA. (2007). “Conceptual seismic design of regular frames based on the concept of uniform damage”. Journal of Structural Engineering (ASCE) 133(7): 945-955.
[9] Chopra, A.K. (2012), “Dynamics of structures, Theory and Applications to EarthquakeEngineering”. 4th Edition, Prentice Hall Inc., London.
[10] Leelataviwat, S., Goel, SC. and Stojadinovic´ B. (1999). “Toward performance-based seismic design of structures”. Earthquake Spectra, 15; 435-461.
[11] Lee, SS, and Goel, SC. (2001). “Performance-Based Design of Steel Moment Frames Using Target Drift and Yield Mechanism”. Report No. UMCEE 01-17, Department of Civil and nvironmental Engineering, University of Michigan, Ann Arbor.
[12] Mohammadi, RK., El-Naggar, MH., Moghaddam, H. (2004). “Optimum Strength Distribution for Seismic Resistant Shear Buildings”. International Journal of Solids and Structures, 41: 6597–6612.
[13] Ganjavi, B., Vaseghi Amiri, J., Ghodrati Amiri, G., Yahyazadeh Ahmadi, Q. (2008). Distribution of drift, hysteretic energy and damage in reinforced concrete buildings with uniform strength ratio”. The 14th World Conference on Earthquake Engineering, Beijing, China.
[14] Hajirasouliha, I. and Moghaddam, H. (2009). “New lateral force distribution for seismic design of structures”. Journal of Structural Engineering (ASCE) 135(8): 906–915.
[15] Goel, SC., Liao, WC., Bayat, MR., and Chao, SH. (2010). “Performance-Based Plastic Design (PBPD) Method for Earthquake-Resistant Structures: An Overview”. Structural Design of Tall Special Buildings, 19: 115-137.
[16] Mohammadi, RK., Ghasemof, A. (2015). “Performance-Based Design Optimization Using Uniform Deformation Theory: A Comparison Study”. Latin American of Solids and Structures, Vol. 12.
[17] Ganjavi, B. and Hao, H., (2013). “Optimum lateral load pattern for elastic seismic design of buildings incorporating soil structure interaction effects”. Earthquake Engineering and Structural Dynamics, 42(6):913-933.
[18] Ganjavi, B., (2015). “Optimal Structural Weight for Flexible-Base Buildings under Strong Ground Motion Excitations”. Asian Journal of Civil Engineering, (In press)
[19] Khatib, IF., Mahin, SA., Pister, KS. (1988). “SeismicBehavior of Concentrically Braced Steel Frames, Earthquake Engineering Research Center”. Report no. UCB/EERC-88/01 University of California, Berkeley.
[20] Tremblay, R., Tirca, L. (2003). “Behavior and Design of Multi-Story Zipper Concentrically Braced Steel Frames for the Mitigation of Soft-Story Response”. in: Proceedings of the Conference on Behavior of Steel Structures in Seismic Areas, pp. 471–7.
[21] Yang, C., Leon, R., DesRoches, R. (2008). “Design and Behavior of Zipper-Braced Frames”. Engineering Structures, 30, pp. 1092-1100.
[22] Sabelli, R. (2001). “Research on Improving the Design and Analysis of Earthquake Resistant Steel-Braced Frames”. Earthquake Engineering Research Institute, NEHRP Fellowship Report No. PF2000-9. Oakland, California.
[23] ASCE7-10 (2010). “Minimum Design Loads for Buildings and Other Structures”. American Society of Civil Engineers: Reston, VA.
[24] American Institute of Steel Construction (2005). “Seismic Provisions for Structural Steel Buildings”. AISC Seismic, Chicago.
[25] Mazzoni, S., McKenna, F., Scott, MH., Fenves, GL. (2014). “OpenSEES Command Language Manual, Pacific Earthquake Engineering Research Center”.
[26] Uriz, P., Mahin, S. (2004). “Summary of test results for UC Berkeley special concentric braced frame specimen No. 1 (SCBF-1)”.
[27] SeismoMatch (2014). “A computer program for adjusting earthquake records to match a specific target response spectrum”. Available from:
[28] Chandler, A.M., Lam, T.K. (2001).  “Performance-based design in earthquake engineering: a multi-disciplinary review”. Engineering Structures, No. 23, pp.1525-1543.
Volume 3, Issue 1 - Serial Number 5
February 2015
Pages 43-60
  • Receive Date: 25 June 2015
  • Revise Date: 12 December 2015
  • Accept Date: 13 January 2016
  • First Publish Date: 13 January 2016