Hastighet – vägyta: problemet, kunskapsläget, fördjupad analys och förslag till fortsatt forskning

Ulf Hammarström
Urban Björketun
Mohammad-Reza Yahya

The correlation between speed and road surface condition is of interest for the planning of pavement maintenance on the road network. The costs and the target variables that are affected by this correlation are, in addition to travel time, fuel consumption (vehicle costs), energy and environment.According to previous studies of the road surface influence on the vehicle speed increased rut depth (RUT) and increasing longitudinal road unevenness (IRI) causes decreased vehicle speed. In the description of the road surface macro texture (MPD) is normally also included. There has, however, been a lack of knowledge about the importance of MPD on vehicle speed. The main purpose of the present study was to supplement existing knowledge about the vehicle speed with the importance of MPD.Mean values of ADC, RF, RUT, IRI and MPD, has been calculated for pre-sections of different lengths between 100 metre and 1 000 metre. These averages can sometimes change significantly with changes in section length while the speed data is the same. The sometimes systematic variation is in part a consequence of the positions of the measurement sites (TMS) not being randomly selected.



Cost Benefit Analysis (CBA) workshop in Stockholm

An open seminar and workshop in Stockholm will be held on 25-26 April 2018. The workshop deals with the use of CBA as a basis for decision-making in the public sector. The workshop is organized by, among others, Professor Jan-Eric Nilsson, VTI.



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