Concrete Permeability and Explosive Spalling in Fire

Abstract:

Permeability of concrete is a good indicator of the risk of explosive spalling, concrete with low permeability is more prone to explosive spalling. To study explosive spalling of concrete, experimental tests on the concrete permeability have been carried out at ETH. The influences from temperature and moisture content have been investigated. The permeability of concrete is found to increase with the temperature and to decrease with moisture content. Based on the test results, a permeability model has been proposed. The explosive spalling has been predicted and an engineering boundary permeability for the liability to spalling is recommended to be 2 × 10^-17 m² for a concrete slab heated according to ISO fire curve. The boundary permeability is influenced by moisture content, tensile strength and heating rate.

• Periodical: Key Engineering Materials (Volume 711)
• Pages: 541-548
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.711.541
• Online since: September 2016
• Authors: Fang Xia Lu*, Mario Fontana
• Keywords: Explosive Spalling, High Performance Concrete (HPC), Permeability Measurement, Permeability Model

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