Behavior of air-entrained concrete under the compression with constant confined stress after freeze–thaw cycles

Properties of air-entrained concrete under compressive loads with constant confined stress after 0, 100, 200, 300 and 400 cycles of freeze–thaw were studied. The failure characteristic of specimens and the direction of the crack are observed. Based on the test data, the influence of freeze–thaw cycles and lateral compressive stress ratio on the ultimate compressive strength is analyzed, respectively. The relationships between the ultimate compressive strength and freeze–thaw cycles, lateral compressive stress ratio are given, respectively. The unified failure criterion with consideration of the influence of freeze–thaw cycles and stress ratio is proposed. It provides the experimental and theory foundations for strength analysis of air-entrained concrete structures subject to complex loads in cold environment.