用于贮存核废料混凝土断裂能的影响因素分析

为确保核废料贮存的长期耐久性,参照国际材料与结构联合会标准(RILEM),分别在常温和受热150℃后,对混杂纤维混凝土和素高强混凝土进行三点弯曲试验.结果表明:1)受热前,纤维混凝土的断裂能为素高强混凝土SP-13的6.3~12.0倍;受热后,为其12.0~16.7倍;2)大尺寸钢纤维A和C对混凝土能量吸收方面的作用优于小尺寸钢纤维B和聚丙烯纤维;钢纤维C(剪切压痕型)对混凝土断裂能的改善效果优于钢纤维A(剪切螺纹型)和钢纤维B(超短超细型);3)综合利用弯曲韧性指标以及断裂能极差、方差对比分析,钢纤维A和C适用于核废料混凝土容器材料.

Analysis of Influencing Factor on Fracture Energy of Concrete Containers for Nuclear Waste

The antifracture property of concrete container for nuclear waste was investigated to ensure its long-time durability. According to RILEM Standard the three-point-bending test was carried out comparatively for the hybrid fiber reinforced concrete and the plain high-strength concrete (SP-13) at normal temperature and after 150°C heating. The results showed that the fracture energy of the former is 6.3-12.0 times higher than the latter before heating and 12.0-16.7 times higher than the latter after heating. The big-size steel fibers (types A and C) are superior to both the small-size steel fibers (type B) and polypropylene fibers in absorbing fracture energy, and the type C steel fibers (shear-indented type) is superior to type A (shear-threaded type)and type B (ultra-short/fine type)in improving the fracture energy. Based on the comprehensive flexure toughness index and the comparative analyses of range and variance, a conclusion is drawn that the types A and C are applicable to the materials to make concrete containers for nuclear waste.