Abstract: The structure of concrete shaft lining is easily corroded in underground complex environment.In order to study the change of the compressive strength and the flexural strength after suffering composite salt disaster solutions corrosion，C70 high strength concrete test specimens were prepared and composite salt disaster solutions with three different concentrations were compounded.The compressive strength and the flexural strength of the concrete test specimens were tested after dipping them into mixture solution and drying them for many times.The test results showed that the change laws of the compressive strength and the flexural strength of the high strength concrete are different after dipping them into water and mixture solution.The compressive strength and the flexural strength are increased in the water，and the compressive strength raises faster in the early time but gradually keeps stable in the later time，while the flexural strength changes suddenly from the sixth month to the seventh month.The compressive strength and the flexural strength of high strength concrete increase in corrosion solutions and then decline.The higher corrosion solution concentration is in the mixture solutions，the quicker the strength declines in the later.The change law of the flexural strength is more complex than that of the compressive strength.

Key words: High strength concrete, Composite salt disaster, Damage