Abstract
This paper aims to show the relations between the time reliability and the functional hierarchy of a road network. For given functions of links, two measures of network hierarchy are proposed. The network User Equilibrium with variable demand and stnct link capacity constraint is applied for calculating travel times between an OD pair of the network with some degraded links. Reliability is defined as the probability of whether travel time is kept within an acceptable level, and an approximation algorithm common for calculating reliability models is proposed. Numerical examples suggest that improving functional hierarchy will increase the time reliability of a road network
