混杂纤维ECC的纤维分布规律及力学性能研究

Study on the fiber distribution and mechanical properties of hybrid fiber ECC

在聚乙烯醇(PVA)纤维高延性水泥基材料(ECC)中混掺入钢纤维,试验研究了不同纤维掺量下混杂钢-PVA纤维ECC中两种纤维的分布情况及其对材料抗弯和抗压力学性能的影响.结果表明:随着钢纤维掺量增大,PVA纤维和钢纤维的分散系数均呈上升趋势,且两种纤维的倾角均倾向于小角度分布,钢-PVA纤维混杂在改善纤维分散及取向方面展现出协同效应;混杂纤维ECC在弯曲作用下的峰值荷载和延性均高于单掺纤维体系,钢纤维适量时,混杂纤维ECC的延性随纤维掺量增加不断提升;此外,钢-PVA纤维混杂也可提高ECC的抗压强度和韧性.

Steel fibers were added into the polyvinyl alcohol(PVA)fiber reinforced engineered cementitious composites(ECC).The distribution of PVA fibers and steel fibers in hybrid fiber ECC with different fiber contents and their influence on the flexural and compressive properties of ECC were experimentally investigated.The results showed that with the increase of steel fiber content,the dispersion coefficient of PVA fiber and steel fiber increases simultaneously,and both of their fiber inclination tends to be distributed towards a small angle.The combination of steel fiber and PVA fiber is conducive to the distribution of fibers in the matrix.The peak load and ductility of hybrid fiber ECC under flexure are higher than that of mono fiber system.When a suitable dosage of steel fiber is incorporated,the ductility of hybrid fiber ECC can be continuously improved with increasing fiber content.Furthermore,the compressive strength and toughness of ECC can be also enhanced by blending PVA fibers and steel fibers.