The Properties of Route Catchments in Orbital – Radial Cities

In this paper we consider the analytical and geometric properties of route catchments in urban areas in which the transport network consists of a combination of radial routes converging on the city centre and one or more major orbital routes around the city. After defining the basic concepts, we examine in detail the analytical and geometric determination of quickest routes through the city centre versus orbital routing and how these vary with location, speed, and urban transport provision. The results are useful in explorations of urban traffic management policies and for testing the general effectiveness of long-term urban network planning strategies.