Permeability of ultra high performance fiber reinforced concretes (UHPFRC) under high stresses

Ultra High Performance Fiber Reinforced Concretes (UHPFRC) present outstanding mechanical properties and a very low permeability which make them very attractive for the rehabilitation of existing structures and for new conceptions. UHPFRC are characterized by a significant tensile strain hardening (multiple cracking stage) that can be used to optimize the mechanical performance of composite structural elements. In order to validate this assumption, permeability tests were carried out on UHPFRC specimens previously submitted to various levels of tensile deformation with progressive damage. Based on permeability results, it was possible to define maximal tensile deformations whereby the water permeability of a specific UHPFRC remains low for various exposure conditions.