Influence of Applied Loads on the Permeability Behavior of Ultra High Performance Concrete with Steel Fibers

Ultra high performance concrete (UHPC) with steel fibers not only possesses the higher compressive strength can be up to above 100MPa, but also has better tensile strength and ultimate strain because of the addition of steel fibers compared with ordinary concrete. However, the permeability behavior of UHPC is frequently ignored in the durability dsign or repair, especially for that with a mass of cracks after suffering short-lived vibration, shock or explosion. This paper is developed to investigate the permeability behavior of UHPC after suffering tensile and compressive loadings, and the water as well as chloride permeability are determined. The results show applied tensile and compressive loadings increase the water and chloride permeability of UHPC. Particularly for the UHPC after suffering high loading damage, the increase of permeability becomes more obvious. Self-healing treatment is also applied to the UHPC with loading damage, and the permeability resistance of UHPC is improved by the treatment of self-healing, which provides an effective method to repair the UHPC with loading damage. In addition, the relation between permeability behavior and applied loads or cracks development are established in this paper, which can be used to evaluate the permeability behavior of UHPC suffered loading damage.