贮存核废料用混杂纤维混凝土弯曲性能试验研究

Test Research of the Flexural Property of Hybrid Fiber Concrete Used for Store Nuclear Waste

为确保核废料运输安全以及长期耐久性,采用正交化配比设计,在混凝土中单掺和混掺钢纤维、聚丙烯纤维、粉煤灰,分别在常温下和受热150℃后进行弯曲韧性试验,通过极差和方差分析,量化了各掺料类型和掺量对于混凝土韧性的影响效果:纤维类型和掺量对于高性能混凝土开裂后力学性能的改善效果更加明显,受热后这-特征更为显著;长度较长、剪切螺纹型的钢纤维A在受热前后阻裂增韧效果均最佳;随着纤维掺量的增加,混掺钢纤维混凝土的弯曲性能基本呈现增强趋势,若总掺量相近,常温下混掺钢纤维混凝土弯曲性能优于单掺,受热后二者性能相近。

To ensure the carrying safety and long-term durability of nuclear waste, the tests of flexural properties were carried out respectively at normal temperature and after being heated to 150℃ using orthogonal mix proportion design and incorporating steel, polypropylene hybrid fiber, fly ash or steel fiber solely in the concrete. Based on gradation and variance analyses, different kinds of admixtures and their effects on toughness of concrete are quantified. Fiber type and incorporation can improve the mechanical properties of high performance concrete effectively after cracking, which is more remarkable after being heated. Steel fiber A with sheared threads has the best effect on anti-cracking and toughening at pre-and post heating. With the increase of fiber incorporations, the flexibility of hybrid steel fiber concrete increases basically. The hybrid steel fiber is better than steel fiber with single incorporation in flexural properties at normal temperature, but no difference after being heated.