Abstract: In order to study the effect of basalt fiber and cellulose fiber mixing on the mechanical properties of concrete, the different basalt fiber lengths (6 mm, 12 mm, 30 mm) and different fiber contents (2.7 kg/m³, 4.0 kg/m³, 5.4 kg/m³) were analyzed by cube compression, splitting tensile and flexural strength test. The results indicate that compressive strength, splitting tensile strength and flexural strength were increased after adding a reasonable content of hybrid fiber. When the content of basalt fiber and cellulose fiber is 4 kg/m³ and 1.6 kg/m³, respectively, the cube compression, splitting tensile and flexural strength are increased by 13.94%, 35.46% and 18.75%, respectively, than that of the ordinary concrete. When the basalt fiber length is 12 mm and the content is 4 kg/m³, the fiber reinforced concrete shows a good enhancement effect. And with the increase of the content, the strength of fiber concrete increases first and then decreases. When the content of cellulose is 1.6 kg/m³, the effect of concrete is the best.

Key words: hybrid fiber, mechanical properties, fiber length, fiber content