Free speeds are defined as the speeds at which vehicles are driven when the drivers are not influenced by other vehicles. In general only some of the drivers in a traffic stream will be able to drive at their free speed. A method has developed to estimate the distribution of free speeds from the speeds of free and non- free vehicles on a cross- section.The method has been evaluated by using two simple simulation models and is applied to data from high flow two- lane rural roads. It was found that a large part of the free speeds are higher than the speed limit. Free speeds in rush hours tend to be somewhat higher than speeds during the rest of the day.
Samenvatting