Evaluation of a Seismic Collapse Assessment Methodology Based on the Collapsed Steel Buildings Data in Sarpol-e Zahab, Iran Earthquake

Mohammad Mahdi Maddah, Sassan Eshghi


The collapse evaluation of the seismically vulnerable structures is very important in any earthquake risk reduction program. There are several analytical methods currently available to assess the collapse capacity of structures under earthquake ground motions. Severe earthquakes in cities provides a unique opportunity to evaluate the effectiveness of the seismic collapse assessment methods. On November 21, 2017, an earthquake with the moment magnitude of 7.3 and the PGA of 0.69 g occurred in about 37 kilometers northwest of Sarpol-e Zahab region (Kermanshah, Iran). This earthquake caused the collapse of significant numbers of low and mid-rise steel structures. In this paper, an attempt is made to examine the efficiency of an approximate incremental dynamic analysis (IDA) method to estimate the collapse capacity of conventional steel structures. To this purpose, two partially collapsed steel structures are selected. Both two structures are comprised of an ordinary moment resisting frame system in one direction, and a braced frame system in other perpendicular direction. The dimensions and permanent displacements of these structures have been measured on-site. These buildings are modeled in a finite element program and analyzed by modal pushover analysis in two major directions, and the SDOF models are extracted. In the next step, the SDOF models are analyzed by the IDA method under the selected earthquake records. The median and dispersion of collapse capacity of the structures are calculated from the approximate IDA results. Finally, the collapse probability of these structures is calculated under the maximum considered earthquake (MCE), determining the uncertainties based on FEMA P695 relation and engineering judgments. The results show the development of simplified and inexpensive methods for collapse assessment is crucial to be implemented to identify existing killer buildings in cities prone to major earthquakes.


Sarpol-e-Zahab (Kermanshah) Earthquake, Collapse Assessment, Steel Buildings, Pushover Analysis, Collapse Capacity, Collapse Probability

Full Text:



Standard No. 2800 (2014) Iranian Code of Practice for Seismic Resistant Design of Buildings. Fourth Revision, Road, Housing and Urban Research Center, Tehran.

Shafei, B., Zareian, F., and Lignos, D.G. (2011) A simplified method for collapse capacity assessment of moment-resisting frame and shear wall structural systems. Engineering Structures, 33(4), 1107-1116.

Han, S.W. and Chopra, A.K. (2006) Approximate incremental dynamic analysis using the modal pushover analysis procedure. Ear thquake Engineering and Structural Dynamics, 35(15), 1853-1873.

Maddah, M.M. and Eshghi, S. (2018) Developing a simplified method to seismic collapse probability evaluation of mid-rise steel moment resisting frames. 11th International Congress on Civil Engineering, University of Tehran, Article No. 1347, Tehran, Iran.

Brozovic, M. and Dolsek, M. (2014) Envelopebased pushover analysis procedure for the approximate seismic response analysis of buildings. Earthquake Engineering & Structural Dynamics, 43(1), 77-96.

IIEES (2017) Report of Earthquake Sarpol-e Zahab. 5th Edition, Volume 1, International Institute of Earthquake Engineering and Seismology Iran, Tehran.

FEMA (2009) Quantification of Building Seismic Performance Factors, FEMA P695. Washington, DC: Federal Emergency Management Agency.

Vice Presidency for Strategic Planning and Supervision (2014) Instruction for Seismic Rehabilitation of Existing Buildings - No. 360- (First revision), Office of Deputy for Strategic Supervision Department of Technical, Iran, Tehran.

IIEES (2018) Suggested Hints of IIEES for Selecting Design Earthquake and Site Type in Sarepol-e Zahab City. International Institute of Earthquake Engineering and Seismology, Tehran, [Online]. Available: http://www.iiees.ac.ir/fa/.

Vamvatsikos, D. and Cornell, C.A. (2002) Incremental dynamic analysis. Earthquake Engineering and Structural Dynamics, 31(3), 491-514.

ASCE (2013) Seismic Rehabilitation of Existing Buildings ASCE/SEI 41-13. American Society of Civil Engineers, Reston, Virginia.

FEMA 273 (1997) NEHRP Guidelines for the Seismic Rehabilitation of Buildings. Federal Emergency Management Agency.

Mazzoni, S., McKenna, F., Scott, M.H., and Fenves, G.L. (2006) The Open System for Earthquake Engineering Simulation (OpenSEES).

Lignos, D.G. and Krawinkler, H. (2010) Deterioration modeling of steel components in support of collapse prediction of steel moment frames under earthquake loading. Journal of Structural Engineering, 137(11), 1291-1302.

Fajfar, P. (1999) Capacity spectrum method based on inelastic demand spectra. Earthquake Engineering and Structural Dynamics, 28(9), 979-994.

Office of National Building Regulations (1392) National Building Regulations of Iran - The Sixth Issue, Loads on the Building. Ministry of Housing and Urban Development, Iran, Tehran.


  • There are currently no refbacks.