Urban traffic-network performance: flow theory and simulation experiments

Thesis/Dissertation · Wed Jan 01 04:00:00 EST 1986

OSTI ID:5281431

Williams, J C

Performance models for urban street networks were developed to describe the response of a traffic network to given travel-demand levels. The three basic traffic flow variables, speed, flow, and concentration, are defined at the network level, and three model systems are proposed. Each system consists of a series of interrelated, consistent functions between the three basic traffic-flow variables as well as the fraction of stopped vehicles in the network. These models are subsequently compared with the results of microscopic simulation of a small test network. The sensitivity of one of the model systems to a variety of network features was also explored. Three categories of features were considered, with the specific features tested listed in parentheses: network topology (block length and street width), traffic control (traffic signal coordination), and traffic characteristics (level of inter-vehicular interaction). Finally, a fundamental issue concerning the estimation of two network-level parameters (from a nonlinear relation in the two-fluid theory) was examined. The principal concern was that of comparability of these parameters when estimated with information from a single vehicle (or small group of vehicles), as done in conjunction with previous field studies, and when estimated with network-level information (i.e., all the vehicles), as is possible with simulation.

• Research Organization: Texas Univ., Austin (USA)
• OSTI ID: 5281431
• Country of Publication: United States
• Language: English

Related Subjects

29 ENERGY PLANNING, POLICY, AND ECONOMY
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320200* -- Energy Conservation
Consumption
& Utilization-- Transportation
CONTROL
MATHEMATICAL MODELS
NETWORK ANALYSIS
PARAMETRIC ANALYSIS
SENSITIVITY
SIMULATION
TRAFFIC CONTROL
URBAN AREAS