【摘要】 采用预制裂缝的三点弯曲试件,应用光弹性贴片法研究了不同纤维掺量活性粉末混凝土RPC200的断裂性能。实验获取了光弹贴片所显示的裂缝扩展全过程,由光弹性条纹分析了不同纤维掺量试件的初裂荷载及临界有效裂缝长度的变化规律。实验表明,利用光弹性贴片法可以有效的获取钢纤维混凝土裂缝扩展的全过程;随着钢纤维掺量的增加,试件的初裂荷载和峰值荷载得到相应提高,且峰值荷载呈近似线性的增加;当纤维掺量为1%时,临界有效裂缝长度值最大;纤维掺量继续增加,其分布均匀性下降,试件的韧性降低,临界有效裂缝长度减少。更多还原

【Abstract】 Fracture properties of steel fiber reinforced reactive powder concrete(RPC200) were investigated based on photoelastic coating method.Three-point flexural beams with prepared crack were employed in the test.Complete crack propagation process of concrete displayed as interference fringes on photoelastic coatings was obtained.The relations between initial cracking load and critical effective crack length and fiber volume were analyzed based on photoelastic fringes.Experiment results indicate that along with the growth of fiber volumes,both the initial cracking load and the peak load increase,moreover the peak load increases linearly.For RPC with 1% steel fibers volume fraction,the critical effective crack length has achieved its maximum value.When the fiber volume is more than 1%,its distribution uniformity decreases,which leads to decline of the ductility and the critical effective crack length.更多还原