Laboratory Investigation of Compacted No-Fines Concrete for Paving Materials

In this study the physical and engineering characteristics of various no-fines concrete mixtures are investigated. No-fines concrete mixtures subjected to impact compaction are studied under unconfined compression, indirect tension, and static modulus of elasticity; and the results are interpreted as functions of mixture proportions. The effect of impact-compaction energies, consolidation techniques, mixture proportions, curing types, and testing conditions on physical and engineering properties are presented. The abrasion characteristics and resistance to freezing and thawing of no-fines concrete are also discussed. It was found that the strength of no-fines concrete is strongly related to its mixture proportion and compaction energy. A sealed compressive strength of 20.7 MPa (3,000 psi) can readily be achieved with an aggregate cement ratio of 4.5:1 or less and a minimum compaction energy of 165 J/m 3 (4,303 ft-lb/cu ft). The splitting tensile-compressive relationship followed a pattern similar to that of conventional concrete. No-fines concrete had a lower modulus of elasticity than conventional concrete. The ultimate drying shrinkage of compacted no-fines concrete was found to be approximately 280 × 10 −6 , about half that typically expected in conventional concrete. Air-entrained no-fines concrete exhibited a higher resistance to freezing and thawing than non-air-entrained mixtures.