Location

London

Event Website

http://www.csce2016.ca/

Description

Post-earthquake fires (PEF) especially in densely populated urban areas have been catastrophic in recent seismic events. It appears to be an important design load which has not been considered critical by most design standards. Moreover, current performance-based seismic design philosophy permits certain level of damage to a structure based on the assumed design seismic hazard. These damaged structures are extremely vulnerable to post-earthquake fires. Even after the outbreak of fire, the structural integrity of the damaged structure must be intact for sufficient duration enabling the firefighters to evacuate and extinguish the fire in the affected building. The recent performance-based design, necessitates evaluation of the fire resistance level of earthquake damaged building with or without the outbreak of post-earthquake fire. In this study an integrated seismic and thermal analysis model was developed using the sequential thermal–structural analysis scheme using the finite element program, ABAQUS. A simple portal frame was considered to investigate the global behaviour of the frame and determine post-earthquake fire resistance. A 2D transient heat transfer analysis was conducted and the transient nodal temperatures across the structural elements cross sections were stored for subsequent thermal structural analyses. The state of earthquake inflicted damage, corresponding to desired performance level was realized using pushover analysis. The results of the simplified 2D model matched reasonably well with that of 3D finite element model considered for validation study. The developed model is being used for subsequent study to investigate the multi-story moment resisting frames with fire scenarios resulting in asymmetric heating of the frame.


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Jun 1st, 12:00 AM Jun 4th, 12:00 AM

STR-866: NON LINEAR FINITE ELEMENT MODEL FOR POST-EARTHQUAKE FIRE PERFORMANCE EVALUATION OF STEEL PORTAL FRAMES

London

Post-earthquake fires (PEF) especially in densely populated urban areas have been catastrophic in recent seismic events. It appears to be an important design load which has not been considered critical by most design standards. Moreover, current performance-based seismic design philosophy permits certain level of damage to a structure based on the assumed design seismic hazard. These damaged structures are extremely vulnerable to post-earthquake fires. Even after the outbreak of fire, the structural integrity of the damaged structure must be intact for sufficient duration enabling the firefighters to evacuate and extinguish the fire in the affected building. The recent performance-based design, necessitates evaluation of the fire resistance level of earthquake damaged building with or without the outbreak of post-earthquake fire. In this study an integrated seismic and thermal analysis model was developed using the sequential thermal–structural analysis scheme using the finite element program, ABAQUS. A simple portal frame was considered to investigate the global behaviour of the frame and determine post-earthquake fire resistance. A 2D transient heat transfer analysis was conducted and the transient nodal temperatures across the structural elements cross sections were stored for subsequent thermal structural analyses. The state of earthquake inflicted damage, corresponding to desired performance level was realized using pushover analysis. The results of the simplified 2D model matched reasonably well with that of 3D finite element model considered for validation study. The developed model is being used for subsequent study to investigate the multi-story moment resisting frames with fire scenarios resulting in asymmetric heating of the frame.

http://ir.lib.uwo.ca/csce2016/London/Structural/41