Direct tensile behavior of high performance fiber reinforced cementitious composites (HPFRCC) at high strain rates between 10 s-1 and 30 s-1 was investigated using strain energy frame impact machine (SEFIM) built by authors. 6 series of HPFRCC combining three variables including two types of fiber, hooked (H) and twisted (T) steel fiber, two types of fiber volume content, 1 % and 1.5 %, and two types of matrix strength, 56 MPa and 81 MPa, were investigated. The influence of three variables on the high strain rate effects on the direct tensile behavior of HPFRCCs was analyzed based on the test results. All series of HPFRCCs showed strongly sensitive tensile behavior at high strain rates, i.e., much higher post cracking strength, strain capacity, and energy absorption capacity at high strain rates than at static rate. However, the enhancement was different according to the types of fiber, fiber volume content and matrix strength: HPFRCCs with T- fibers produced higher impact resistance than those with H- fibers; and matrix strength was more influential, than fiber contents, for the high strain rate sensitivity. In addition, an attempt of prediction the DIF of post cracking strength for HPFRCCS considering the influences of fiber type and matrix strength was made.
