This paper discusses the nature, size, and causes of traffic congestions on Dutch motorways, and the traffic and road engineering measures that can be taken to reduce these congestions as much as possible. To extend the existing traffic space one or more traffic lanes can be added to the highway cross section. In this respect the following geotechnical and pavement technical measures are discussed: a) light embankment materials; b) stone columns; c) vacuum consolidation; d) vertical drainage; e) asphaltic concrete pavement with grid; f) cement concrete pavement; g) block pavement. To make better use of the existing traffic space the following traffic engineering measures can be taken: a) use of the hard shoulder; b) redivision of the highway cross section; c) tidal flow; d) variable direction signing; e) local adjustments of the geometry; f) ramp metering; g) homogenizing the traffic flow via signalising recommended speeds; h) very accurate traffic control; i) reconsideration of bridge openings; j) rush-hour service buses. To reduce the nuisance for the traffic when maintenance works are carried out a number of measures are discussed, such as carrying out more of the maintenance activities at night, and improvement of the co-ordination and information dissemination. Finally, the attention for the maintenance aspects already during the design stage of pavements is discussed. For the covering abstract of the conference see IRRD No 862419.
Abstract