Samenvatting
This paper discusses the causes of congestion (recurrent, roadworks and incident) on the English trunk road network, and how they can be identified and quantified from an analysis of historic journey time data patterns and knowledge of the location and timings of roadworks. A case study is used to illustrate the methodology. The approach provides patterns for recurrent journey times and delays with and without roadworks, which can be used to provide more accurate driver information both before and during the trip. For the covering abstract see ITRD E134653.