Naslov
Numerical analysis of spalling of concrete cover at high temperature

Autori
Ožbolt, Joško ; Periškić Goran ; Reinhardt, Hans-Wolf ; Eligehausen Rolf

Izvornik
Computers and Concrete, an International Journal (1598-8198) 5 (2008); 279-293

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
concrete ; high temperature ; explosive spalling ; thermo-hygro-mechanical model ; microplane model ; finite elements

Sažetak
In the present paper a 3D thermo-hygro-mechanical model for concrete is used to study explosive spalling of concrete cover at high temperature. For a given boundary conditions the distribution of moisture, pore pressure, temperature, stresses and strains are calculated by employing a three-dimensional transient finite element analysis. The used thermo-hygro-mechanical model accounts for the interaction between hygral and thermal properties of concrete. Moreover, these properties are coupled with the mechanical properties of concrete, i.e. it is assumed that the mechanical properties (damage) have an effect on distribution of moisture (pore pressure) and temperature. Stresses in concrete are calculated by employing temperature dependent microplane model. To study explosive spalling of concrete cover, a 3D finite element analysis of a concrete slab, which was locally exposed to high temperature, is performed. It is shown that relatively high pore pressure in concrete can cause explosive spalling of concrete. The numerical results indicate that the governing parameter that controls spalling is permeability of concrete. It is also shown that possible buckling of a concrete layer in the spalling zone increases the risk for explosive spalling.

Izvorni jezik
Engleski

Znanstvena područja
Građevinarstvo, Temeljne tehničke znanosti

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