A DOUBLE LAYERED CRCP : ENVIRONMENTAL, ECONOMIC AND SOCIAL ASSESSMENT

摘要

The technique of double-layered concrete or two lift paving is applied either to obtain a high-quality top layer in terms of safety and driving comfort, either to use lower quality and thus less expensive materials in the lower lift, or for both reasons at the same time. In Europe this technique is commonly applied in Austria where recycled crushed concrete from former pavements is used in the bottom layer. Driven by the growing environmental consciousness and a desire for innovation, the Flemish Road Authorities followed the Austrian example and planned a trial worksite on a 3 km section of the highway N49 (E34) in Zwijndrecht near Antwerp. The construction took place in two phases: in the direction of Ghent in 2007 and in the direction of Antwerp in 2008. The double advantage of using reclaimed, less expensive aggregates and obtaining a quieter and smoother surface will undoubtedly promote this type of sustainable pavements. The paper will conclude with an assessment of environmental, economic and social aspects for the double layered pavement in comparison with traditional construction techniques.