钢纤维增强再生混凝土动态冲击力学性能试验研究

Experimental Study on Dynamic Impact Mechanical Properties of Steel Fiber Reinforced Recycled Concrete

为研究钢纤维增强后的再生骨料混凝土(RAC)的动态力学性能,采用φ74 mm变截面分离式霍普金森压杆(SHPB)在高应变率下进行动态冲击压缩试验,分析不同钢纤维掺量下动态抗压强度、动态增长因子(DIF)、动态冲击韧性等力学参数对动态应变速率的敏感性.结果表明:与普通再生混凝土相比,钢纤维再生混凝土动态抗压强度、动态增长因子等力学参数具有明显的应变率增强效应,并且这种增强效应随着钢纤维含量的增加而增加.钢纤维再生混凝土有10%~80%左右的动力强度增幅.不同钢纤维掺量的再生混凝土应变率敏感性有一定差异,不同应变率下材料的应变率敏感性也有所不同.

Inorder to study the dynamic mechanical properties of steel fiber reinforced recycled aggregate concrete(RAC),the dynamic impact compression test was carried out by a split Hopkinson pressure bar(SHPB)with a variable cross section of 74 mm at high strain rate. The sensitivities of dynamic compressive strength,dynamic growth factor(DIF),dynamic impact toughness and other mechanical parameters to dynamic strain rate under different steel fiber contents were analyzed. The results show that compared with ordinary recycled concrete,the mechanical parameters such as dynamic compressive strength and dynamic growth factor of steel fiber reinforced recycled concrete have obvious strain rate enhancement effect,and this enhancement effect increases with the increase of steel fiber content. The dynamic strength of steel fiber reinforced recycled concrete increases by about 10% to 80%. The strain rate sensitivities of recycled concrete reinforced with different steel fiber contents are different,and the strain rate sensitivities of the materials are also different under different strain rates.