This paper considers how the costs of congestion can be identified and addressed and offers help for the engineer in designing the most appropriate level of capacity. The paper identifies and describes a method for assessing the level of service, or stress, withing the network and then goes on to put forward a method for defining the timing and scale of highway provision necessary to relieve stress. The level of service concept is simplified through the use of three thresholds which define the operational performance of a highway: a) capacity threshold; b) congestion threshold; and c) design threshold. The methodology described is principally concerned with dual 3-lane motorways. Its application to dual motorways. Its application to dual 2-lane motorways and all-purpose carriageways with various speed limits is described. Other applications are discussed.
Samenvatting