This report presents suggestions for new speed-flow relationships for motorways (MV), low standard motorways (4F), oncoming lane separated highways with grade separated intersections (MML), oncoming lane separated highways with at grade intersections (MLV), and two-lane highways. The analysis conducted resulted in suggestions to decrease the free flow speed and the travel speed at higher flows for most of the road categories. For motorways also a decrease in capacity is suggested. For oncoming separated highways (both MML and MLV) are minor changes of the capacity suggested. The suggested capacity value is 1550 vehicles/h independently of speed limit and lane/road width. For MML and MLV a new model, that uses the share of the road that allows overtaking as input, has been used for the first time. For two-lane highways the number of road width categories have been decreased to three for roads with speed limit of 80 km/h or higher; and to four for roads with a speed limit of 70 km/h. The reason is that road width do not seem to have as large influence on the travel speed as before. This also led to minor adjustments of the capacity for some of road width categories. Trafikverket seems to have accepted all suggestions and incorporated these into the new version of “Effect calculations for road facilities”. However, it is important to remember that this report presents data and suggestions and that the official Swedish speed-flow relationships are presented in Trafikverket’s “Effect calculations for road facilities”. (Author/publisher)
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