Ultra Fast Track Concrete Paving Recent Belgian Research and Applications

In Belgium, most of the actual road works deal with rehabilitation, maintenance and repair. For the Road and Traffic Administrations, the limitation of the traffic disturbance is one of the major challenges. Thanks to the technique of rapidly hardening concrete, known as ‘fast-track concrete paving’, cement concrete pavements are repaired and reopened for traffic within less than three days. This technique is used as well for local repairs as for the rehabilitation of longer road sections. In general, the base layer is also renewed during these rehabilitation works. The aim of the concrete mix is to reach a compressive strength on cores after 30 to 36 hours of 40 N/mm², which is the limit to allow traffic according to the Belgian standard specifications. The materials used are currently available in the mixing plants without addition of fly ash or silica fume. This paper describes the results of the preliminary research program, carried out at the Department of Civil Engineering, K.U.Leuven as well as the results obtained on a test section of a regional road near Brussels.