基于图像处理的纤维分布与取向分布对水泥基材料弯曲性能的影响

聚乙烯醇(PVA)纤维增强水泥基材料的弯曲性能与纤维在水泥基体内的分布和取向分布相关。采用抛光断面后涂荧光粉的显微成像法,基于图像处理程序对PVA纤维在水泥基材料中的分布和取向分布进行量化测定,对不同基体结构特征影响纤维分布的机理进行了讨论。结合弯曲试验结果,研究了纤维分布和取向分布对材料弯曲性能的影响。纤维分布测定结果表明,均匀的基体结构特征利于纤维的分布,同时对于材料组分和加工制作过程完全相同的试件,纤维分布系数越大,试件的弯曲强度与韧性越大;纤维取向分布测定结果表明,乱向分布的纤维当其长度方向与抛光断面方向的角度接近90°分布概率越大,试件的弯曲韧性也越大。

Effects of Fiber Distribution and Orientation Distribution Based on Image Processing on Bending Properties of PVA Fiber Reinforced Cementitious Composites

Fiber distribution and orientation distribution play a key role in bending property of PVA fiber reinforced cementitious composites. PVA fibers distribution and orientation distribution based on image processing was quantitatively measured by fluorescence microscope images methods. Meanwhile, the effects of different formation of cementious matrix due to component adjusting on fibers distribution were discussed. Moreover, effects of fiber distribution and orientation distribution on bending properties of PVA fiber reinforced cementitious composites were comprehensively studied. The results of the distribution of PVA fibers showed that uniformity of the formation of cementious matrix was beneficial to good fibers distribution. At the same time, higher fiber distribution coefficient would lead to higher strength and ductility of the specimens with the same component and processing. The results of the orientation distribution of fibers showed that high distribution probability of orientation angle approaching to 90° between fiber length direction and the polishing surface direction contributed to high ductility of the specimens.