This report describes studies of the effect of various road improvements on safety and journey time and speed. The alternatives dealt with are: a new road reserved for motor traffic (cost 31 million sw crs) and two improvement levels. Level one comprises: road widening, adjustments of convex radii, visibility improvements, channelisation, high post lighting in intersections, traffic signalized crossings for cyclists and pedestrians and a separate road for pedestrians, cyclists and moped riders. (cost 9 million sw crs.) level 2: road widening, adjustments of convex radii, climbing lane, alignment change, lighting, game preserves, reconstruction of two close t-junctions to one four road junction. (cost 22 million sw crs.) in the accident studies the prediction model, based on road width, horizontal curve radius and gradient, and a model based on minimum visibility were used. The journey time and speed effects were studied in a simulation test. The result showed that a new road reserved for motor traffic reduced accidents and journey times more than improvements of the corresponding section of the old road. Improvement level 2 reduced accidents related to channelisation, game preserves and profile adjustments. The journey time and speed improved with road widening and introduction of climbing lanes, especially at high traffic flows. Finally a calculation of the first year profit from the improvements is presented. /TRRL/

  • Corporate Authors:

    Swedish National Road Administration

    Fack S-10220
    Stockholm 12,   Sweden 
  • Publication Date: 1977-9


  • Swedish

Media Info

  • Features: Figures; References; Tables;
  • Pagination: 63 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00179897
  • Record Type: Publication
  • Source Agency: Swedish National Road and Traffic Research Institute
  • Report/Paper Numbers: Monograph
  • Files: ITRD, TRIS
  • Created Date: Sep 27 1978 12:00AM