Development of a zero-span tensile test for HPFRCC used for structural repairing

The most important characteristic of High Performance Fiber Reinforced Cement Composites (HPFRCC) is the formation of multiple fine cracks in tension, which provides novel mechanical properties, such as strain hardening behavior. For these reasons, HPFRCC can be widely used in retrofitting and repairing of existing concrete structures. In a repair application, the crack in the substrate induces localized fracture within HPFRCC. Elongation performance of HPFRCC on an existing crack, which represents resistance against the localized fracture, is required in repair applications. This research proposes the zero-span tensile test to evaluate the crack elongation performance for HPFRCC, and examines the effects of test conditions (i.e. artificial crack width, steel plate thickness, and specimen thickness) on the zero-span tensile test results. This paper also reveals that the crack elongation obtained from the test is lower than the deformation capacity evaluated by ordinary uni-axial tensile tests.