Abstract: Uniaxial compression test and Brazilian splitting test were carried out on chopped basalt fiber concrete with different volume content and length to analyze the influence of basalt fiber on the mechanical properties of concrete. The results showed that the addition of basalt fiber changes the failure mode of concrete from brittle failure to ductile failure. The cube compressive strength of concrete at each age increases in varying degrees when the content of basalt fiber is 0. 05% and 0. 10%,and decreases when the content of basalt fiber is increased to 0. 20%;The splitting tensile strength of concrete at each age increases to varying degrees with different content. Basalt fiber significantly improves the compressive toughness of concrete cube. For the concrete with a curing age of 28 days,when the volume content is 0. 05%,the basalt fiber with a length of 12 mm has a significantly better effect on the compressive toughness of concrete than the fiber with a length of 18 mm.

Key words: basalt fiber concrete,volume content,fiber length,uniaxial compressive strength,splitting tensile strength,compressive toughness