Fracture energy and parameter of crack propagation model of high-performance fiberreinforced concrete under direct tension

Abstract

Fracture energy and parameter of crack propagation model of HPFRCs under direct tension were determined in this paper based  on test results. Three fiber types embedded in HPFRCs with their same volume content of 1.5 vol.% as follows: short smooth fiber, long hooked fiber, and hybrid fiber (including 1.0% long hooked fiber blended with 0.5% short smooth fiber). The long hooked and short smooth fiber have their aspect ratios 35/0.5 mm và 13/0.2 mm, respectively. The test results showed that, the energy fracture of HPFRC containing hybrid fiber revealed the highest fracture energy, in both zones within and beyond of the peak of stress-displacement response cures, although the fiber amounts added in HPFRCs were identical. The length of cohesive crack of HPFRCs, an important parameter of crack propagation model under direct tension, was also assessed and discussed.

Keywords: HPFRC; fracture energy; cohesive crack length; crack propagation