Abstract

The elastic properties of cementitious composites reinforced by nano-tailored hybrid fibers are analyzed using a micromechanical method. The microstructural feature of the hybrid fiber is that uniformly aligned carbon nanotubes (CNTs) are grown radially on the circumferential surface of carbon fibers (CFs). The CNT waviness and CNT/cement interfacial region are considered. The predictions are compared with experiments, which guarantee the validity of the model. The mechanical properties of cementitious composites, especially in transverse direction, are enhanced due to the radial growth of CNTs on the CFs. The CNT/cement interfacial zone may have a significant effect on the elastic behavior of the nano-tailored hybrid fiber-cement composites. As the mechanical properties of interphase are higher than those of the cement matrix, increasing the interphase thickness causes an improvement in the elastic and shear moduli. The CNT non-straight shape decreases the transverse elastic modulus.

摘要

使用微观力学方法分析了纳米定制混合纤维增强的水泥基复合材料的弹性性能。混合纤维的微观结构特征是均匀排列的碳纳米管（CNT）在碳纤维（CF）的圆周表面呈放射状生长。考虑了 CNT 波度和 CNT/水泥界面区域。将预测与实验进行比较，保证了模型的有效性。由于 CNT 在 CF 上的径向生长，增强了水泥基复合材料的机械性能，特别是在横向方向上。CNT/水泥界面区可能对纳米定制混合纤维-水泥复合材料的弹性行为有显着影响。由于中间相的力学性能高于水泥基体，增加相间厚度会导致弹性模量和剪切模量的改善。CNT 的非直线形状降低了横向弹性模量。