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According to ACI's Cement and Concrete Terminology (ACI 116R-90), no-slump concrete is freshly mixed concrete exhibiting a slump of less than 1/4 inch. Zero-slump concrete is defined in the same document, as concrete of stiff or extremely dry consistency showing no measurable slump after removal of the slump cone. And negative-slump concrete is concrete of a consistency such that it not only has zero slump but still has zero slump after additional water is added.
It was determined that the rollers were very effective in compacting the dry-mix concrete and that the strength properties, compressive strength and flexural strength, were somewhat higher than would have been obtained with a conventional mix of the same cement content having a slump in excess of 1 inch. The surface smoothness, surface texture, and riding quality of the pavement were considered adequate for wearing surfaces of secondary roads and streets, haul roads, service entrances, tank trails, ect., and as a base for any pavement system. Indications are that considerable cost reductions in the construction of portland cement pavements can be realized by use of dry (zero-slump) concrete mixtures placed and spread by base course or asphalt spreaders and compacted with heavy vibratory rollers.