This study attempted to develop models for stress-strain relationships in tension and compression of concrete damaged by freezing and thawing cycles (FTC). Concrete specimens in shapes of cylinders and prisms were tested with the ASTM FTC test and in an…
This study attempted to develop models for stress-strain relationships in tension and compression of concrete damaged by freezing and thawing cycles (FTC). Concrete specimens in shapes of cylinders and prisms were tested with the ASTM FTC test and in an environmental chamber where temperature and moisture conditions can be controlled as desired. After a certain number of FTC, the specimens were mechanically loaded and concrete strains were carefully measured. The test results indicate a rather linear relationship between the reduced dynamic elastic modulus and the reduced tensile strength and stiffness. The reduction in compression is different from that in tension. There is no longer linear relationship between the dynamic elastic modulus and the reduction of compressive strength. Instead the reduction in both strength and elastic modulus shows a rather linear dependency with the plastic tensile strain caused by FTC. Therefore, the stress-strain relationship under compression of FTC-damaged concrete is formulated as a function of remaining tensile strain caused by FTC. The stress-strain relationship under tension is formulated as a function of relative dynamic elastic modulus. In addition, numerical simulation with meso-scale material models was conducted and the results show good prediction of the reduction on strength and stiffness of FTC-damaged concrete.