Several different experiments,including freezing-thawing,freezing-thawing+drying-wetting,and drying-wetting,in salt solution and in water respectively,were designed to determine the durability of concrete.The durability damage features of concrete in the above experiments were studied.It is demonstrated that the damage extent of concrete under freezing-thawing and freezing-thawing+drying-wetting in salt solution is larger than that in water.Thus,freezing-thawing and freezing-thawing+drying-wetting in salt solution are stricter and more effective methods to evaluate the durability of concrete in salt-existing environment in cold regions.The damage extent of concrete under freezing-thawing+drying-wetting shows an ultra-superposition effect.The order of concrete durability deterioration degree in these experiments is determined.It shows that effects of multi-damage factors are greater than those of single-damage factor.