Pavement Edge Drain Barriers in the Rehabilitation of Existing Roads (Experiments and Field Results)

The research and development on the new type of products known of the appellation "pavement edge drain-barriers" was carried out in France together by producers, road construction firms and the French road administration (the Laboratoire Central des Ponts et Chaussees - LCPC and the Service d'Etudes Techniques des Routes et Autoroutes - SETRA). The initial studies, undertaken in the first half of the 1980s, permitted to define the technique of edge drain-screens. The effectiveness of drain-screens was evaluated, thanks to experimental workings, on the basis of monitoring of the pavements behavior during a seasonal cycle by comparison of results obtained on equipped sections and non equipped sections. Practical conclusions concerning the use of these new products have also been drawn up from these experiments. The experiments the most complete were particularly performed on two sites in France: the RN 176 (Cotes d'Armor) in 1985, and the RN 171 (Mayenne) in 1986. The results of these experiments described in this paper show the effectiveness of the edge drain-screens for the internal drainage of water penetrating in the subgrade and in the pavement. The improvement of the stiffness of soil and unbound materials of the structure by reduction of pore pressure and water content is highlighted. For the covering abstract see ITRD E118503.