纤维混凝土核废料贮存容器可靠度分析

以复掺聚丙烯-玄武岩纤维混凝土为研究对象，对试块进行室内单轴压缩蠕变试验研究，采用Burgers模型拟合蠕变方程.通过等时应力-应变曲线，分析材料弹性模量随时间递减的变化规律，结合试验获取的极限应变和拉压比，最终得到抗拉强度随时间的变化规律作为可靠度评判的标准.其次，运用ANSYS软件分析得到贮存容器300a服役期内时变衰变热-力耦合作用下温度应力.最后，考虑热工参数的不确定性，运用蒙特卡洛随机抽样法得到核废料贮存容器的失效概率.结果表明:失效概率随服役期呈上升趋势，100a内增幅较大，100~300a增长趋势变缓，300a时达到064%.证明纤维混凝土材料自身劣化是导致贮存容器耐久性下降的重要因素.

Reliability Analysis of Fiber Concrete Containers for Nuclear Waste Storage

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.