磁铁矿防辐射超高性能混凝土制备及性能研究

核技术在造福人类的同时,也产生了无处不在的核辐射,而当前的普通防辐射混凝土并不能完全满足安全防护的需要.本文基于最紧密堆积理论,采用不同比例的磁铁矿替换河砂,制备了防辐射超高性能混凝土(UHPC),并对其工作性能、力学性能、微观结构、孔结构,以及γ射线屏蔽性能进行了研究.结果表明,磁铁矿的加入使得UHPC的流动性以及抗...

Preparation and Properties of Ultra-High Performance Concrete for Radiation Protection of Magnetite

While the nuclear technology benefits mankind, it also produces nuclear radiation everywhere. However, the current ordinary radiation-proof concrete cannot completely meet the needs of safety protection. In this paper, based on the tightest packing theory, the ultra-high performance concrete (UHPC) for radiation protection was prepared by replacing river sand with different proportions of magnetite, and its working performance, mechanical properties, microstructure, pore structure, and γ-ray shielding performance were studied. The results show that the fluidity and compressive strength of UHPC slightly decrease with the addition of magnetite, but the decline is small. As the replacement proportion of magnetite increases, the γ-ray shielding performance of UHPC is improved obviously. When the replacement proportion of magnetite is 100% (volume fraction), the linear attenuation coefficient of UHPC increases by 31.3%, while the half-value layer and ten-value layer all decrease by 23.8%. The addition of magnetite does not change the type of hydration products, but improves the pore structure of UHPC and effectively reduces its porosity.