混杂纤维增强应变硬化水泥基复合材料抗弯冲击性能

Flexural impact behavior of hybrid fiber-reinforced strain hardening cementitious composites

  • 摘要: 首先研究了在准静态作用下不同纤维掺量及基体强度的混杂纤维增强应变硬化水泥基复合材料(SHCC)的抗压和抗弯性能。实验结果表明,混杂钢纤维可大幅提高SHCC材料的强度,其中抗压强度和抗弯强度分别提高了10.1%和13.9%。其次,采用落锤式冲击系统开展了混杂纤维增强SHCC在不同冲击高度下的动态抗弯性能试验。研究发现,混杂钢纤维的动态抗弯强度比单一纤维SHCC提高了10%~36%,具有明显的应变率效应。混杂纤维增强SHCC能量耗散与弯曲变形之间存在线性关系。最后,提出利用五维表征雷达图综合评估混杂纤维增强SHCC的成本和力学性能,并建议了最佳配合比。

     

    Abstract: The compressive and flexural properties of hybrid fiber-reinforced strain hardening cementitious composites (SHCC) with different fiber volume fractions and matrix strengths under quasi-static effects were firstly studied. The experimental results show that the hybrid steel fibers can significantly improve the strength of SHCC materials, in which the compressive strength and flexural strength are increased by 10.1% and 13.9%, respectively. Subsequently, dynamic flexural performance tests of hybrid fiber-reinforced SHCC at different impact heights were carried out using a drop hammer impact system. It is found that the dynamic flexural strength of hybrid steel fibers increases by 10%-36% compared with single-fiber SHCC, with a significant strain rate effect. A linear relationship exists between energy dissipation and bending deformation of hybrid fiber-reinforced SHCC. Finally, this paper proposes a comprehensive evaluation of the cost and mechanical properties of hybrid fiber-reinforced SHCC using a five-dimensional characterization radar plots, and suggests the optimal mix ratio.

     

/

返回文章
返回