In order to study the stress-strain relationship of concrete under sulfate attack and freeze-thaw cycles, the uniaxial compression experiments of concrete subjected to freeze-thaw cycles in water, and mass fraction of 5% sodium sulfate, 5% magnesium sulfate solution were carried out. The effects of sulfate solution and freeze-thaw cycles on the peak stress, peak strain, elastic modulus and stress-strain curve of concrete were investigated．Furthermore, the mechanical property of the damage layer of concrete was analyzed. The results show that the stress-strain curve is flat and moves to the right with freeze-thaw time increases. The rising step of stress-strain curve rises slightly, and the curve is concave when concrete subjected to 300 freeze-thaw cycles in the sulfate solution. Along with the freeze-thaw cycle increases, the peak stress and elastic modulus of concrete decrease, and the peak strain increases gradually. This phenomenon is more obvious when concrete exposed to magnesium sulfate solution, and the frost resistance of concrete is the worst. Through regression analysis, the uniaxial compressive stress-strain curve equation under sulfate solution and freeze-thaw cycles is proposed to fit the test results. Moreover, the peak stress of the damage layer of concrete is obtained when exposed to different freeze-thaw cycles.
