A New Seismic Design Method for Steel Structures
A seismic design methodology for steel building frames which combines the advantages of the well-known force-based and displacement-based seismic design methods in a hybrid force/displacement design scheme is proposed. The method controls structural performance by first transforming user-specified values of the interstorey drift ratio (non-structural damage) and local ductility (structural damage) to a target roof displacement and then calculating the appropriate strength reduction factor for limiting ductility demands associated with the target roof displacement. The main characteristics of the method are: (1) it treats both drift and ductility demands as input variables; (2) it does not use a substitute single degree of freedom system; (3) it makes use of conventional elastic response spectrum analysis and design; (4) it includes the influence of the number of storeys; (5) it recognizes the influence of the type of the lateral load resisting system (moment resisting frame or concentrically braced frame); (6) it recognizes the influence of geometrical (setbacks) or mass irregularities.
KeywordsPeak Ground Acceleration Seismic Design Strength Reduction Factor Roof Displacement Moment Resist Frame
The first two authors are grateful for the support provided to them through the “K. Karatheodoris” research program of the University of Patras, Greece. All the authors acknowledge helpful discussions with Professors S.A. Anagnostopoulos, M.N. Fardis and N. Makris.
- 2.CEN (2004) EN 1998-1:2004 Eurocode 8. Design of structures for earthquake resistance, part 1: general rules, seismic actions and rules for buildings. European Committee for Standardization, BrusselsGoogle Scholar
- 3.FEMA (1997) Federal Emergency Management Agency. NEHRP guidelines for the seismic rehabilitation of buildings, Report FEMA-273, Washington, DCGoogle Scholar
- 4.SEAOC (1995) Structural Engineers Association of California. Vision 2000 – A Framework for performance based earthquake engineering, Vol. 1. SEAOC, Sacramento, CAGoogle Scholar
- 5.Karavasilis TL, Bazeos N, Beskos DE (2006a) A hybrid force/displacement seismic design method for plane steel frames. In: Mazzolani F, Wada A (eds), Behavior of Steel Structures in Seismic Area, Proceedings of STESSA Conference, pp 39–44, Yokohama, Japan, August, Taylor & FrancisGoogle Scholar
- 6.Karavasilis TL, Bazeos N, Beskos DE (2006b) A hybrid force/displacement seismic design method for plane steel frames. Proceedings of 1st European conference on earthquake engineering and seismology (1st ECEES), Geneva, Switzerland, 3–8 September, Paper No 1013Google Scholar
- 7.Zotos PC, Bazeos N (2009) Estimation of seismic response in planar x-braced multi-storey steel frames. Proceedings of 2nd international conference on computational methods in structural dynamics and earthquake engineering, Island of Rhodes, Greece, 22–24 June, Paper CD364Google Scholar
- 9.Karavasilis TL, Bazeos N, Beskos DE (2008a) Drift and ductility estimates in regular steel MRF subjected to ordinary ground motions: a design-oriented approach. Earthq Spectra 24(2):431–151Google Scholar
- 12.Karavasilis TL, Makris N, Bazeos N, Beskos DE (2010) Dimensional response analysis of multi-storey regular steel MRF subjected to pulse-like earthquake ground motions. J Struct Eng (ASCE), in pressGoogle Scholar
- 13.Maison BF (1992) PC-ANSR. A computer program for nonlinear structural analysisGoogle Scholar