ANALYSIS OF TRANSPORTATION NETWORK CAPACITY RELATED TO DIFFERENT SYSTEM CAPACITY CONCEPTS

Abstract

In transportation, capacity has traditionally been measured at individual elements of the network, such as links (rail lines, road segments and waterway etc.) and nodes (terminals and signalized intersection, etc.). These measures do not constitute the transportation network capacity. Recently, Wong and Yang (1997) proposed the concept of network reserve capacity to estimate the transportation network capacity, but the concept is restricted to a common multiplier for all O-D pairs. In this study, the concepts of ultimate capacity and practical capacity (with a non-uniform O-D growth) are applied to the transportation problem to relax the limitation of the reserve capacity concept; thus, the concepts can yield information regarding the spatial distribution of the demand pattern. The definitions of three different network capacity concepts and their models will be described. The analysis of network capacity for three different concepts is provided to demonstrate their features.