Abstract: According to the result of creep test on the fiber concrete which mixed basalt fibre and polypropylene fiber， creep equation was fitted through Burgers model. The progressively decreasing modulus of elasticity of fiber concrete with time was summarized through isochronous stressstrain curve， together with the ultimate strain and ratio of tensile and compressive strength tensile compressive tested at the laboratory， the variations of tensile strength with time were got as the reliability evaluation criterion. Second， ANSYS software was used to analyze the temperature stress of the container wall under the thermomechanical coupling condition in the service of 300 years. At last， taking account of uncertainty of thermal parameters， the failure probability of tensile stress arise from decaying heat was solved by MonteCarlo method. The failure probability tends to rise， increasing greatly within 100 years， and increasing slightly between 100a and 300a， until a failure probability of 064% after 300a. This proved that the degradation of fiber concrete was the key factor that caused the decline of durability for nuclear waste storage container.

Key words: hybrid fiber reinforced concrete, nuclear waste storage, creep property, decaying heat stress, failure probability