Pavements on the base of polymer-modified drainage concrete

Abstract

Drainage concrete on the base of cement as the sole binder is a long standing subject in research since more than 30 years. The material is already used in the application area of filter tubes, sound proofing walls, cycle tracks, footpaths and traffic surfaces like parking lots. Up to now this material could not be used for roads, motorways or racing tracks because of the missing mechanical stability of these pavements. The use of a second binder, a polymer emulsion, in addition to cement can improve the mechanical stability, the resistance to deformation, that means: no rutting. The polymer emulsion should exhibit a very good cement compatibility, a glass transition temperature above RT and in the fresh mortar–concrete it should induce a higher flexural tensile strength. The emulsion used in the experiments to optimise a recipe for practical uses is on the monomer-base of styrene–acrylics (Mowilith LDM6880). The drainage concrete can be worked out in strength classes ( B≤25 N mm −2) in mixtures with water:cement ratios of about 0.24:0.26, which contain double-broken and screened chippings, cement and emulsion only. Those pavements exhibit high noise reduction, high sound absorbency in the range of 5–7 dB(A), high drainage effect, e.g. no sheets of spray from wheels, no aquaplaning, reduced black ice formation in winter and a good long term stability. The void content is adjustable between 15 and 25%.