MANAGING CONGESTION, POLLUTION, AND PAVEMENT CONDITIONS IN A DYNAMIC TRANSPORTATION NETWORK MODEL

This paper presents a dynamic model that characterizes the changing st ates of traffic volumes, design capacities, and pavement conditions in a transportation network's major commuting arteries. It also portrays the evolution of two system-wide effects-total vehicle miles travelle d (VMT) and volatile organic compound (VOC) emissions-and accounts for lagged adjustments in travel behavior in its disequilibrium formulati on. The model can be employed in optimal control exercises to determin e what steps ought to be taken, when and where, and by how much in ord er to achieve planning objectives. Specifically, the model can be used to determine optimal combinations of traffic demand management measur es, lane widening, and highway maintenance for achieving desired peak- period congestion levels, reducing VMT and VOC emissions to levels man dated by the Clean Air Act Amendments (CAAA), and keeping pavement con ditions at acceptable serviceability ratings. Information on intertemp oral tradeoffs between planning objectives, now required by the Interm odal Surface Transportation Efficiency Act (ISTEA), is generated in so lutions to such exercises. We discuss how the model can be operational ized and illustrate its practicability with a small empirical example. (C) 1998 Elsevier Science Ltd. All rights reserved.