NUMERICAL MODEL FOR CONCRETE EXPOSED TO HIGH TEMPERATURE

Harinadha Reddy, Ananth Ramaswamy

Abstract: Fire in concrete structures causes serious damage in the form of deterioration of strength properties and may lead to failure of the structures. Estimating the extent of damage is very important for repair or retrofitting of the concrete structures. In the present study a Hygro-thermo-mechanical model is developed to estimate the pore pressure, temperature and displacements. These parameters are treated as state variables which intern vary with the extent of the dehydration process when concrete is exposed to high temperature. Concrete is treated as a deformable, multiphase porous material. The model is developed based on the poromechanics concepts. Phase changes and chemical reactions (dehydration) are taken into account in the model development. The model is a coupled chemo-hygro-thermo-mechanical process (accounting for the extent of dehydration). The model accounts for the characteristic of various phases of concrete such as moisture, energy and transport phenomena. Evolution of material properties (porosity, permeability, strength properties) with the extent of temperature of concrete is considered in the model

Keywords: Concrete, High Temperature, Pore Pressure, Hygro Thermo Mechanical Model, Damage

DOI: https://doi.org/10.15623/ijret.2015.0425035