Sage Journals: Discover world-class research

Abstract

Different seismic codes propose different criteria to detect vertical stiffness irregularity. However, due to ambiguity in the evaluation of these criteria, usually designers ignore the control of these criteria altogether. This study tries to provide simple and easy to evaluate numerical criterion to detect vertical stiffness irregularity. Evaluation of the current codes criteria reveal that satisfaction of the code criteria provides different levels of safety against deformation localization for different stories and different structures. Then, it is shown that it is possible to evaluate a conservative estimate of drift for nonlinear analyses using the results of linear elastic analyses. Finally, to detect the possibility and extent of probable deformation localization in different stories due to vertical stiffness irregularity, a numerical criterion using the results of linear static analysis is proposed.

Keywords

vertical stiffness irregularity localization of deformations response history analysis equivalent static analysis

Get full access to this article

View all access options for this article.

References

AISC (2005). Specification for Structural Steel Buildings, American Institute of Steel Construction, Chicago, Illinois, USA.

Al-Ali

A.A.K.

and Krawinkler

(1998). Effects of Vertical Irregularities on Seismic Behavior of Building Structures, Report, Department of Civil and Environmental Engineering, Stanford University, California, USA.

Chintanapakdee

and Chopra

A.K.

(2004). “Seismic response of vertically irregular frames: Response history and modal pushover analyses”, Journal of Structural Engineering, ASCE, Vol. 130, No. 8, pp. 1177–1185.

Das

(2000). Seismic Design of Vertically Irregular Reinforced Concrete Structures, PhD Thesis, North Carolina State University, USA.

Eurocode 8 (2001). Design of Structures for Earthquake Resistance Part 1, European Committee for Standardization, Brussels, Belgium.

Fragiadakis

Vamvatsikos

and Papadrakakis

(2006). “Evaluation of the influence of vertical stiffness and strength irregularities on the seismic response of a 9 storey steel frame”, Earthquake Engineering and Structural Dynamics, Vol. 35, No. 12, pp. 1489–1509.

International Code Council (2006). International Building Code, Falls Church, Virginia, USA.

Iranian Code (2005). Iranian Code of Practice for Seismic Resistant Design of Buildings, Standard No. 2800, 3rd Edition, Building and Housing Research Center, Iran.

Magliulo

Ramasco

and Realfonzo

(2002). “Seismic behavior of irregular in elevation plane frames”, Proceeding of the 12th World Conference on Earthquake Engineering, London, UK.

10.

Mazzolani

F.M.

and Piluso

(1997). “Review of code provisions for vertical irregularity”, Proceeding of STESSA, Kyoto, Japan, August.

11.

NEHRP (2003). Recommended Provisions for Seismic Regulations for New Buildings and other Structures (FEMA 450), Building Seismic Safety Council, The National Institute of Building Sciences, Washington DC, USA.

12.

OpenSEES (2006). Open System for Earthquake Engineering Simulation, Pacific Earthquake Engineering Research Center (PEER). (http://opensees.berkeley.edu/) Valmundsson

E.V.

and Nau

J.M.

(1997). “Seismic response of building frames with vertical structural irregularities”, Journal of Structural Engineering, ASCE, Vol. 123, No. 1, pp. 30–41.

A Numerical Criterion to Detect Vertical Stiffness Irregularity

Abstract

Keywords

Get full access to this article

References