Ultimate Strength Analysis for a Concrete Beam after a Sustained Building Fire

Abstract:

More than 90% of the buildings in Taiwan use reinforced concrete (RC) structures. It is crucial to human life and property to determine whether the RC structure is safe after fire damage. However, it is impossible to obtain fire thermal parameters quantitative data from actual building fires. Therefore, numerical simulation software that simulates fire scenarios was used to model fires for fire protection engineering. Beam strength decreases because of high temperature. To obtain precise beam temperature profiles in a building fire, this study used the fire model FDS and field model PHOENICS software to simulate fire development and beam inner temperature variation. Fire scenarios and beam surface temperatures in a room fire were analyzed by the FDS fire model. Beam boundary temperatures were transferred into the PHOENICS field model to compute the detailed temperature profile within the beam. The structural strength was estimated by using beam various cross-section temperatures to investigate dynamic ultimate bending moment of a RC beam in a room fire. Through the various simulations and calculations, this investigation obtained the influence of various beam positions, fire intensity, fire duration and fire damage sustained (whether two or three faces) by a RC beam after a building fire.

• Periodical: Advanced Materials Research (Volume 566)
• Pages: 331-335
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.566.331
• Online since: September 2012
• Authors: Kuo Da Chou, Cherng Shing Lin, Chia Chun Yu, Shih Cheng Wang
• Keywords: FDS, Field Model, Fire, Numerical Simulation, Reinforced Concrete (RC) Beam

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