玄武岩纤维增强珊瑚骨料混凝土的动态劈拉性能试验研究

Experimental study on dynamic splitting tensile properties of basalt fiber reinforced coral aggregatee concrete

为研究玄武岩纤维增强珊瑚骨料混凝土(BFCAC)的动态劈拉性能,通过20组100个试件的动态劈拉试验,分析了玄武岩纤维对BFCAC动态劈拉性能的影响机理,建立了动态劈拉强度的统计概率模型。结果表明:随着应变率增大,BFCAC的动态劈拉强度和动态耗能均逐渐增大。当玄武岩纤维掺量分别为0、0.1%、0.2%和0.3%时,随着应变率增大,BFCAC的动态强度增长因子变化范围分别为1.51~2.99、1.74~3.26、2.07~3.45、2.31~3.67,动态耗能增大比例变化范围分别为62.13%~139.39%、73.88%~150.99%、66.15%~162.14%、90.01%~168.11%,表明玄武岩纤维提高了BFCAC动态劈拉性能的应变率效应;玄武岩纤维降低了BFCAC的动态劈拉破坏程度,且其滑移阻抗随着应变率增大而增大,提高了BFCAC的抗冲击性能。建立的动态劈拉强度统计概率模型可有效表征BFCAC动态劈拉强度的统计分布规律。

To study the dynamic splitting tensile properties of basalt fiber reinforced coral aggregate concrete(BFCAC),the influence mechanism of basalt fibers on the dynamic splitting tensile properties was analyzed through the dynamic splitting tensile experiment of 100 BFCAC specimens in 20 sets,and the statistical probability model for the dynamic splitting tensile strength was established.The results show that as the strain rate increases,the dynamic spliting tensile strength and dynamic dissipated energy gradually increase.When the content of basalt fibers is O,0.1%,0.2%,and 0.3%,respectively,as the strain rate increases,the range of dynamic increase factors is 1.51-2.99,1.74-3.26,2.07-3.45,and 2.31-3.67,respectively,and the range of the increase proportion of dynamic dissipated energy is 62.13%-139.39%,73.88%-150.99%,66.15%-162.14%,and 90.01%-168.11%,respectively,indicating that basalt fibers improve the strain rate effect of dynamic splitting tensile properties of BFCAC.Basalt fibers reduce the degree of dynamic splitting tensile failure of BFCAC,and their slip impedance increases with the increase of strain rate,improving the impact resistance of BFCAC.The established statistical probability model for dynamic spliting tensile strength can effectively characterize the statistical distribution law of dynamic splitting tensile strength of BFCAC.