High-temperature performance of damaged reinforced concrete columns under post-earthquake fires

Abstract

Post-earthquake fires (PEF) are a frequent phenomenon of earthquakes and usually causes severe damage to reinforced-concrete (RC) columns. To determine the high-temperature performance of RC columns damaged by PEF, the geometric-damage forms of concrete columns after an earthquake are mainly classified as cracking, concrete spalling, and residual deformation on the basis of existing hazard and experimental data. Full-scale seismic-damage column tests were performed to analyse the failure mode of components at a high temperature. Subsequently, the relative depth of cracks, thickness of concrete spalling, relative height of spalling, and residual deformation were proposed as geometric-damage parameters to calculate the thermal-field distribution. Finally, according to the relation between the geometric-damage parameters and the bearing capacity, equations for predicting the high-temperature bearing capacity of PEF concrete columns were established.

Keywords:

• Failure mode
• geometric-damage
• high-temperature bearing capacity
• high-temperature performance
• Post-earthquake fire
• residual deformation
• thermal field

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

The authors wish to acknowledge their gratitude towards the Major Program of the National Natural Science Foundation (No. 51590914) (in China), the National Natural Science Foundation Project (No. 51578450, No. 51378225) (in China), National Key R&D Program of China (No. 2017YFC0803300), the Program for Innovative Research Team in University of Ministry of Education of China (No. IRT_17R84), International cooperation projects of Shaanxi Province (No. 2019KW-047) (in China) and Shaanxi Province Housing and Urban Construction Technology Research and Development Project of China (No. 2015-K145).