Title:
Modeling of Thermal Spalling for a GFRP-Reinforced Concrete Slab
Author(s):
Jun Wang and Yail J. Kim
Publication:
Symposium Paper
Volume:
356
Issue:
Appears on pages(s):
72-87
Keywords:
agent-based model; glass fiber reinforced polymer; heat transfer; slab; thermal spalling
DOI:
10.14359/51737248
Date:
10/1/2022
Abstract:
This paper presents an analytical approach to simulate the heat transfer and thermal spalling of a glass fiber-reinforced polymer (GFRP)-reinforced concrete slab. Employing an agent-based model, differential equations are solved with the thermal properties of concrete and insulation layers. The model provides pore pressure and temperature-dependent stress to predict concrete spalling, which is assumed to occur when the pressure exceeds the tensile strength of the concrete. With an increase in external temperature, the thermal conductivity and thermal diffusivity of the slab system alter. The degree of heat transfer to the reinforcement level is retarded with the presence of insulation that can better preserve the bond between the concrete substrate and GFRP. A comparative study on the insulation and extra concrete cover shows that their initial performance is similar, whereas bifurcations are noticed due to the different thermal characteristics. Notwithstanding the marginal implications of tensile strength in the concrete, the likelihood of spalling rises as the concrete strength increases.
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