钢纤维类型和掺量对高强混凝土力学性能的影响

INFLUENCE OF STEEL FIBER FORMA AND DOSAGE ON MECHANICAL PROPERTIES OF HIGH STRENGTH CONCRETE

混凝土加入钢纤维被认为是一种有效增加混凝土韧性,提高力学性能的手段。本文通过掺加不同类型和不同掺量的钢纤维,测试了混凝土的抗压、抗折和劈拉强度,研究了纤维类型和掺量对力学性能的影响。结果表明,混凝土抗压强度随着镀铜微丝型钢纤维掺量的增加而增大,而端钩型、铣削型和熔抽型钢纤维的种类和掺量对混凝土抗压强度的影响并不显著。无论掺加何种类型纤维,纤维的掺入对抗折强度的贡献均大于对抗压强度的贡献。混凝土劈拉强度对纤维的端钩、直径、长度和表面状态等因素敏感,纤维类型对混凝土的劈拉强度影响显著。

The adding of steel fiber was considered to be effective way to increase toughness and mechanical properties of concrete. Compressive strength, flexural strength and splitting tensile strength of concrete were tested by adding different volume fraction and different kinds of steel fiber in this study, and the influence of steel fiber forms and dosage was studied. Results showed that the compressive strength increases with the increase of mixing amount of copper covered small scale steel fiber, while the forms and dosage of end hooked steel fiber, milling steel fiber and melt extracted steel fibers were less obvious effects on compressive strength. No matter what kinds of steel fiber added, the contribution of steel fiber on flexural strength was greater than that of on compressive strength. Splitting tensile strength of concrete was sensitive to hooked or not, diameter, length and surface state of steel fiber, and steel fiber forms have a significant effect on splitting strength.