User inequity implications of road network vulnerability

Abstract: An important purpose of the road transport system is to allow people to commute in efficient and reliable ways. For various undesired reasons, however, link capacities are sometimes reduced or links are closed completely. To assess and reduce the risk of such events, a key issue is to identify road links that are particularly important, i.e. roadswhere disruptionswouldhave particularly severe consequences. ăis paper presents a method for incorporating user equity considerations into a road link importance measure. As a complement to measuring the total increase in vehicle travel time, we also measure the disparity in the distribution among individual users. ăese two components are combined to form an equity-weighted importancemeasure. We study the properties of this measure both analytically and in a full-scale case study of the Swedish road network. Amain result is that increasing the weight put on the equity aspect transfers importance from themain roads to smaller local roads. ăe use of the measure in transport policy and planning is discussed