【摘要】 以应用较为广泛的重晶石和磁铁矿防辐射混凝土为研究对象，探讨了高温对其立方体抗压强度、应力-应变曲线、弹性模量、延性系数和能量耗散系数等力学性能指标的影响。试验结果表明，高温作用下混凝土的力学特性与其骨料性能密切相关；随着温度的升高，两种类型防辐射混凝土的立方体抗压强度、峰值应力和弹性模量逐渐减少，其峰值应变、延性系数和能量耗散系数逐渐增大。同时，重晶石混凝土在300℃以上会出现严重的爆裂现象。然而磁铁矿混凝土具有较好的热稳定性和力学性能，因此其更适合应用于高温环境下混凝土屏蔽层的设计。更多还原

【Abstract】 The effects of high temperatures on the mechanical properties such as the cubic compressive strength,stress-strain curve,elastic modulus,ductility parameter and energy dissipation coefficient of the more widely used barite and magnetite radiation shielding concrete were investigated.Results showed that the mechanical properties of concrete structures subjected to elevated temperatures were strongly correlated with the performances of aggregate.With the increase of temperature,the cubic compressive strength,peak stress and elastic modulus of the two kinds of radiation shielding concrete gradually decreased,and their peak strain and ductility increased gradually.Meanwhile,barite concrete appeared severe concrete spalling phenomenon above 300 ℃,and magnetite concrete had better thermal stability and mechanical properties,thus it was more suitable for the design of concrete shielding layer under high temperature environment.更多还原