The A7 motorway is the North-South road which follows the Rhone Valley from Lyon to Marseille. The motorway is a major regional and European economic artery. The total absence of an alternative replacement route demands extreme care in maintaining the level of availability. Along the section between Valence and Orange, the road bears average daily traffic of 76,000 vehicles/day, with 18% heavy goods vehicles (HGV). Summer traffic regularlyexceeds 150,000 vehicles/day. Every year, the period during which trafficconditions allow for closing off lanes for road work grows increasingly smaller. This road section started operations between 1967 and 1968. It is now nearly 40 years old and requires continual major renovation work. Roadgeometry was initially composed of three 3.50-meter lanes open to trafficand a 3- meter wide emergency lane. The road section was recently equipped with a central median with steel safety guard rails. The disadvantages of lane separation and road marking in traditional methods of roadworks arediscussed. On the A7, ASF have adopted a fresh approach, replacing the central metallic barriers with modular concrete separators and widening the emergency lane to 3.50 m over a 90 km section of the road. This has the advantages of: eliminating the need for lateral shift of the road marking, saving time on the work preparation and traffic resumption phases; drastically reducing maintenance work, cleaning and refurbishment of safety equipment after accidents; Increased safety for contractors and for traffic in both directions; and reduced traffic congestion and improved flows. For thecovering abstract see ITRD E139491.
Abstract