DESIGN AND REHABILITATION OF PCC PAVEMENTS IN NORWAY - A NEW STRATEGY

Abstract

In Norway concrete pavements are used on 2 lane highways with ADT of 5000 to 15000. We use thin pavements, and in our specifications the min. thickness varies from 15 to 20 cm. Today 90% of all passenger cars and 50% of all trucks use studded tires during the winter. Important requirements for pavements therefore are resistance to wear from studs, freezing and thawing and salt, and we must find simple, inexpensive methods to rehabilitate pavements. The use of Silica and other admixtures makes it possible to deliver high strength concrete at reasonable cost. Based on our experience on results from a test road we continue our design using thin pavements. In 1978 modern pavement profilers were introduced in Norway, and we have been experimenting with their use. Today our procedures for rehabilitation include the use of profilers for milling down the pavement. We drive directly on the milled surface until a new milling or resurfacing is performed. Different profilers and the methods of us have been tested to obtain a safe riding surface at reasonable cost. To ensure future maintenance and rehabilitation we are adding 30 to 70 mm to the design thickness of the pavement, depending on future traffic. When the surface develops longitudinal rutting along the wheel tracks, it is removed and the cross-section restored by grinding down with a pavement profiler. This process can be repeated 2 to 3 times.