MODELING FREEZE AND THAW DAMAGE IN CONCRETE DECKS USING DAMAGE MECHANICS

Research has documented that freeze-thaw cycles (FTCs) deteriorate mechanical properties of concrete such as strength and stiffness. This paper presents a general approach to model the changes in these mechanical properties. It also presents a generalized bounding surface approach, where limit surface is allowed to collapse inward and form a new failure surface (residual strength) corresponding to the number of FTCs. Within this formulation, softening equations for strength reduction and the increase in ultimate strain of concrete under FTCs are proposed. Stress-strain curves are obtained and the anisotropic degradation in mechanical properties is captured. The results show a good correlation with experimental data available in the literature.