碳化硼对铁矿石混凝土亚高温后性能的影响研究

Study on the Influence of Boron Carbide on the Properties of Iron Ore Concrete After Sub-high Temperature

以5%的碳化硼等质量取代褐铁矿砂,制备了强度等级C50和密度等级RS2的铁矿石防辐射混凝土,研究了其在不同亚高温温度下的热工性能以及145℃处理5 d前后力学及耐久性能,分析了碳化硼在亚高温前后对铁矿石混凝土性能的影响规律和机理。结果表明:碳化硼的掺入提高了铁矿石混凝土的比热容、导热系数、热扩散系数、抗折强度,但降低了铁矿石混凝土的表观密度、抗压强度;亚高温后,碳化硼的填充效果明显,优化了气泡参数,提高了铁矿石混凝土微观结构的稳定性,有利于减缓铁矿石混凝土耐久性能劣化过快的情况,维持铁矿石混凝土亚高温后的防辐射稳定性。

Iron ore anti radiation concrete with strength grade C50 and density grade RS2 was prepared by replacing limonite ore sand with 5%boron carbide.The thermal performance at different sub-high temperature and the mechanical and durability properties of iron ore concrete before and after being treated at 145℃for 5 d were studied.The influence of boron carbide on the performance of iron ore concrete before and after sub-high temperature was analyzed.The results show that the addition of boron carbide improves the specific heat capacity,thermal conductivity,thermal diffusion coefficient and flexural strength of iron ore concrete,but reduces the apparent density and compressive strength of iron ore concrete.After sub-high temperature,the filling effect of boron carbide is obvious,which optimizes the bubble parameter,improves the stability of the microstructure of iron ore concrete,helps to slow down the deterioration of the durability of iron ore concrete,and maintains the radiation stability of iron ore concrete after sub-high temperature.