Influence of fiber content and reinforcement ratio on the water permeability of reinforced concrete

摘要

In service, reinforced concrete structures undergo various stresses inducing cracks. These cracks provide a preferential path for water and aggressive agents penetration into concrete, which compromises the structural durability by accelerating concrete and steel reinforcement deterioration. In this context, durability of cracked concrete has become an important research topic and can be studied through the permeability of concrete. This research project focuses on the influence of the fiber content and steel reinforcement ratio on the water permeability of reinforced concrete. Water permeability tests were carried out simultaneously with a uniaxial tensile loading applied on reinforced concrete prisms made of high performance concrete (HPC), high performance fiber reinforced concrete (HPFRC) and ultra high performance fiber reinforced concrete (UHPFRC). In service conditions, permeability is reduced by 31, 92 and 99 % for fiber contents of 0.75 % (HPFRC), 1.5 % (HPFRC) and 2 % (UHPFRC) respectively compared with conventional HPC. The increase of steel reinforcement ratio from 1.23 to 2.47 % reduced the permeability by 70 % at service loading.