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.