试件成型方式对纤维分布和弯拉强度的影响

Influence of Specimen Cast Mode on the Steel Fiber Distribution and Flexural-Tensile Strength of Steel Fiber Reinforced Concrete

选取国内定型生产的钢板剪切型钢纤维,研究标准棱柱体试件采用卧式和立式成型方法对混凝土中钢纤维分布形态和钢纤维混凝土弯拉强度的影响.对试件进行切片试验研究表明,钢纤维在混凝土中趋于沿垂直于成型方向分布的规律,分布特征明显受到水泥用量、钢纤维长度和体积分数的影响.对试件进行弯拉强度试验表明,钢纤维对卧式成型混凝土试件弯拉强度的增强作用大于对立式成型混凝土试件弯拉强度的增强作用.研究成果为修订《钢纤维混凝土试验方法》(CECS 13:89)提供了参考.

Selecting the approved products of steel fiber, made by the thin-plate shearing method, the standard prismatic specimen were cast by horizontal and vertical modes to study the distribution states of steel fiber and the flexural-tensile strength of steel fiber reinforced concrete. It is proved by the slice tests of specimen that the steel fiber tends to distribute perpendicular to the cast direction. There are obviously effects of the cement content, the length of steel fiber and the fraction of fiber by volume on the distribution states of steel fiber in concrete. It is also proved by the flexural-tensile tests that the enhancement of steel fiber on the flexural-tensile strength of concrete cast by horizontal mode is larger than that of concrete cast by vertical mode. The research results can be used as reference to revise the standard of test methods of steel fiber reinforced concrete.