论文部分内容阅读
将廉价的微米级CaCO_3晶须引入毫米级钢纤维与聚乙烯醇(PVA)纤维混杂纤维增强水泥基复合材料(HyFRCC),研究CaCO_3晶须对HyFRCC薄板力学性能、破坏形态和尺寸效应的影响,并使用SEM观察HyFRCC微观形貌。试验结果显示,引入晶须后,HyFRCC薄板呈现出良好的弯曲性能及比梁式试件更优良的假性应变硬化和多缝开裂特征,且可以更有效地减小尺寸效应对抗弯强度的影响。微观形貌观察证实掺加晶须后,混杂纤维体系可以在不同尺度上发挥多层次阻裂作用。研究认为,由廉价的CaCO_3晶须部分替代钢纤维和PVA纤维制备的HyFRCC呈现出对板式构件良好的适应性,实现了力学性能优化和经济性提高的双重目标。
The effect of CaCO_3 whisker on the mechanical properties, failure morphology and size effect of HyFRCC sheets was investigated by introducing low-grade CaCO_3 whiskers into the fiber reinforced fiber reinforced composite (HyFRCC) made of millimeter-grade steel fibers and polyvinyl alcohol (PVA) The microstructure of HyFRCC was observed by SEM. The experimental results show that the introduction of whiskers, HyFRCC sheet showed good bending properties and beam specimens than the more excellent pseudo-strain hardening and multi-slit cracking characteristics, and can be more effectively reduce the size effect on the bending strength influences. Micro-morphology observation confirmed that mixed with whiskers, the hybrid fiber system can play a multi-level blocking effect in different scales. According to the research, HyFRCC prepared by partial replacement of steel fiber and PVA fiber with cheap CaCO_3 whiskers shows a good adaptability to plate-type components and achieves the dual objective of optimization of mechanical properties and improvement of economy.