Probabilistic performance-based evaluation of a tall steel moment resisting frame under post-earthquake fires

Purpose This paper aims to develop a framework to assess the reliability of structures subject to a fire following an earthquake (FFE) event. The proposed framework is implemented in one seamless programming environment and is used to analyze an example nine-story steel moment-resisting frame (MRF) under an FFE. The framework includes uncertainties in load and material properties at elevated temperatures and evaluates the MRF performance based on various limit states. Design/methodology/approach Specifically, this work models the uncertainties in fire load density, yield strength and modulus of elasticity of steel. The location of fire compartment is also varied to investigate the effect of story level (lower vs higher) and bay location (interior vs exterior) of the fire on the post-earthquake performance of the frame. The frame is modeled in OpenSees to perform non-linear dynamic, thermal and reliability analyses of the structure. Findings Results show that interior bays are more susceptible than exterior bays to connection failure because of the development of larger tension forces during the cooling phase of the fire. Also, upper floors in general are more probable to reach specified damage states than lower floors because of the smaller beam sizes. Overall, results suggest that modern MRFs with a design that is governed by inter-story drifts have enough residual strength after an earthquake so that a subsequent fire typically does not lead to results significantly different compared to those of an event where the fire occurs without previous seismic damage. However, the seismic damage could lead to larger fire spread, increased danger to the building as a whole and larger associated economic losses. Originality/value Although the paper focuses on FFE, the proposed framework is general and can be extended to other multi-hazard scenarios.

[1]  Spencer E. Quiel,et al.  Modeling steel structures in OpenSees , 2015 .

[2]  Andrew H. Buchanan,et al.  Structural Design for Fire Safety , 2001 .

[3]  Venkatesh Kodur,et al.  Review of post-earthquake fire hazard to building structures , 2008 .

[4]  J. I. Ghojel,et al.  Three-sided heating of I-beams in composite construction exposed to fire , 2005 .

[5]  Spencer E. Quiel,et al.  Closed-Form Prediction of the Thermal and Structural Response of a Perimeter Column in a Fire , 2010 .

[6]  Negar Elhami Khorasani,et al.  A Probabilistic Framework for Multi-Hazard Evaluations of Buildings and Communities Subject to Fire and Earthquake Scenarios , 2015 .

[7]  Stephen Pessiki,et al.  Effect of Earthquake-Induced Damage on the Sidesway Response of Steel Moment-Frame Buildings during Fire Exposure , 2015 .

[8]  Paolo Gardoni,et al.  Fire load: Survey data, recent standards, and probabilistic models for office buildings , 2014 .

[9]  Helmut Krawinkler,et al.  Deterioration Modeling of Steel Components in Support of Collapse Prediction of Steel Moment Frames under Earthquake Loading , 2011 .

[10]  Liming Jiang,et al.  OpenSees Software Architecture for the Analysis of Structures in Fire , 2015, J. Comput. Civ. Eng..

[11]  Jian Jiang,et al.  Modeling of steel frame structures in fire using OpenSees , 2013 .

[12]  Federico M. Mazzolani,et al.  Improvement of Buildings' Structural Quality by New Technologies : Proceedings of the Final Conference of COST Action C12, 20-22 January 2005, Innsbruck, Austria , 2005 .

[13]  L. Ibarra.  Global collapse of frame structures under seismic excitations , 2003 .

[14]  Asif Usmani,et al.  How did the WTC towers collapse: a new theory , 2003 .

[15]  Federico M. Mazzolani,et al.  Post-earthquake fire resistance of moment resisting steel frames , 2003 .

[16]  Spencer E. Quiel,et al.  Parameters for Modeling a High-Rise Steel Building Frame Subject to Fire , 2010 .