摘   要：在混凝土中同时加入钢纤维和纳米矿粉，对比研究了钢纤维和纳米矿粉掺量以及基体强度对钢纤维纳米混凝土劈拉性能和抗折性能的影响规律。结果表明，钢纤维的加入及增大掺量，改善了试件的破坏特征，劈拉和抗折强度均显著增长；基体强度提高的同时，拉压强度比和折压强度比降低；纳米SiO₂和纳米CaCO₃掺量的增大，可小幅度提高劈拉和抗折强度，但脆性也相应提高。钢纤维增强增韧作用、纳米矿粉微填充及促进水化作用共同改善了混凝土的力学性能。

Abstract: Both of steel fibers and nanometer materials are mixed into concrete, then the effects of mix amount of steel fiber and nanometer materials as well as matrix strength on splitting tensile and flexural strength of steel fiber-nanometer material reinforced concrete are investigated. The experimental results show that the failure characteristic, splitting tensile and flexural strength of specimens are improved significantly in the case of mixing with steel fiber and increasing of mix amount of steel fiber; with the increasing of matrix strength, the tension-compression ratio and flexure-compression ratio decreased; with the increasing of mix amount of nanometer SiO₂ and CaCO₃, the splitting tensile, flexural strength brittleness increased to a limited extent. The improved mechanical properties benefited from the effects of reinforcing and toughening for steel fiber, and the effects of filling and promoting hydration for nanometer materials.