Permeability of roller compacted concrete
Water‐permeability measurements were made on 50 mm diameter and 100 mm long cored cylinders obtained from a roller compacted concrete pavement that was 160 mm in average thickness. A triaxial permeability cell was used. The effect of water‐cement ratio, silica fume addition, use of a finer cement, curing technique, etc. on coefficients of permeability were investigated. Roller compacted concrete was found to be considerably more permeable than conventionally proportioned and placed concrete and somewhat more permeable than conventional mass concrete. The use of silica fume and finer cement appeared to reduce the coefficient of permeability to some extent. However, the method of curing did not make any appreciable difference. When observed under a microscope, roller compacted concrete was found to have a number of interconnected compaction voids, hollow aggregate‐paste boundaries, and interfaces that were porous and undeveloped.