Comparison of Seismic Safety and Functionality of Low Rise Important Buildings Designed by the First Three Editions of Iranian Seismic Code

Document Type : Technical Note


University of Zanjan, Zanjan


Buildings with high degree of importance such as hospitals, police stations, fire stations and other vital facilities play a crucial role in crisis and risk management of cities. Therefore, special attention should be paid to design and construction of these buildings in order to maintain their performance during and after the earthquake. Important buildings in Iran is designed according to the Iranian code of practice for seismic resistant design of buildings (ISC). So far, four editions of the code have been published. In this study, improvement of seismic safety of important buildings in the first three editions of ISC are examined and the results are compared with an acceptable level of safety. In this study, a 3-story steel moment resisting frame is selected and designed based on different editions of ISC for high seismic zones. The seismic fragility functions of frames are estimated in all soil classifications of the code. The probability of failure of frames are estimated for Tehran and Tabriz, two major cities located in high seismic zones. Results shows a good improvement in safety of different frames in recent editions of ISC, especially from the first to the second editions due to mandatory of ductile design and increase of the design forces. However, the functionality and safety of buildings do not satisfy the minimum requirements of the code. In addition, the results indicated that the probability of failure of frames located in softer soil types is higher than others. This show that within any code edition, a constant limit of safety was not provided in different soil types. Therefore, an improvement in the spectral acceleration of different soil type is required.


Building and Housing Research Centre (2005) Iranian Code of Practice for Seismic Resistant
Design of Buildings (ISC) - Standard No. 2800. BHRC.
Motamed Sahebi, M. (2009) Critically look to design of very important structures based on ISC's method. 4th Congress on Study of Standard of Seismic Design of Structure (ISC), Building and House Research Centre (BHRC), Tehran, Iran.
Mahmoudi, M. and Ghobadi, A. (2011) Seismic design of very high importance buildings regulations using standard 2800: critical review (technical note). Civil Engineering Infrastructures Journal, 45(3), 365-369.
Behnamfar, F. and Nafarieh, A. (2003) Uncertainties in the application of R factor in seismic code. 3rd Congress on Study of Standard of Seismic Design of Structure (ISC), Building and House Research Centre (BHRC), Tehran, Iran.
Shakib, H. (2000) Vulnerability seismic evaluation of important steel buildings using nonlinear analysis. 5th International Conference of Civil Engineering of Mashhad, Mashhad, Iran.
Nasserasadi, K., Ghafory-Ashtiany, M., Eshghi, S., and Zolfaghari, M.R. (2009) Stochastic approach for developing seismic fragility function and its dispersion in structures. Asian Journal of Civil Engineering, 10(2), 183-200.
Jalayer, F. (2003) Direct Probabilistic Seismic Analysis: Implementing Non-Linear Dynamic Assessments. Ph.D. Thesis, Civil and Environmental Engineering Department, University Stanford, California.
McKenna, F. and Fenves, G.L. (2007) The OpenSees Command Language Manual- Version 1.2. (July 1) [Online] Available: [2012, January 12] Pacific Earthquake Engineering Research Centre, University of California, Berkeley.
HAZUS-MH MR3 (2003) Multi-Hazard Loss Estimation Methodology, Technical Manual. Federal Emergency Management Agency (FEMA), Washington, D.C.
Nasserasadi, K. (2006) Seismic Risk Assessment Methodology for Industrial Facilities; Case study of an Oil Refiner y. Ph.D. Thesis, International Institute of Earthquake Engineering and Seismology (IIEES), Tehran, Iran.
Ghafory-Ashtiany, M. and Nasserasadi, K. (2010) Re-Evaluation of Earthquake Insurance Index in Iran. A Report to Insurance Research Institute, Tehran, Iran.