This paper describes a network level benefit-cost analysis (BCA) system that works in harmony with the assignment method used for traffic forecasting. The BCA system has recently been converted to a PC environment to work in conjunction with the commercial traffic forecasting software package TRIPS (TRansport Improvement Programming System). There is a 'converging' trend in most Australian road agencies to use, or, have preference for, the TRIPS traffic package. Most road agencies are also interested in linking traffic forecasting packages with network RUC evaluation models while at the same time maintaining flexibility in the type of evaluation models that can be adopted. Learning more about the capabilities of the TRAMS evaluation package offers a real opportunity in considering urban RUC evaluation alternatives. A discussion of the key urban RUC evaluation elements in the TRAMS package is presented in this paper. It is within the engine part of the system, where the control data are integrated with the traffic assignment data to produce economic evaluation output that is consistent with the network changes being examined. Delays and costs imposed by intersections are calculated separately and added to the times and costs of travelling on the links. Estimates of road user costs (RUC) are based on levels of congestion and amount of travel, while road characteristics of roughness, grade and curvature are held constant for each capacity indicator. (a)
Abstract