Roundabouts in Continuously Reinforced Concrete Design – Construction

In Belgium, as in many European countries, traffic at major junctions is managed increasingly by constructing right-of-way roundabouts, which allow safer and smoother traffic flow. The intense heavy traffic at these roundabouts induces extreme stresses in the pavement, both as a result of centrifugal forces as well as the overloading exerted by the offside wheels of tilting vehicles. The effects of such stresses include rut formation, the sideways displacement of the wearing course, the loss of surface aggregate, and cracking as a result of insufficient bearing capacity in the road structure beneath the offside wheels. These findings encourage designers to think of ways of using continuously reinforced concrete for the construction of roundabouts, with the result that the first such roundabouts were built in 1995 and are still in excellent condition today. There can be no better demonstration of the suitability of this technique for application on a larger scale. This paper deals with the design and construction specifications of roundabouts in continuously reinforced concrete.