Title

A SIMPLE PHYSICAL PRINCIPLE FOR THE SIMULATION OF FREEWAYS WITH SPECIAL LANES AND PRIORITY VEHICLES

Document Type

Journal Article

Publication Date

1997

Subject Area

operations - traffic, infrastructure - vehicle, infrastructure - bus/tram priority, infrastructure - bus/tram priority, infrastructure - bus/tram lane, infrastructure - traffic signals, mode - bus

Keywords

Traffic simulation, Traffic signal priority systems, Traffic signal preemption, Preemption (Traffic signals), Motorways, Kinematics, Highway traffic, Freeways, Freeway traffic, Freeway operations, Controlled access highways, Bus priority

Abstract

This paper presents a simple physical principle that can be used to solve the kinematic wave problem for freeways with special lanes and priority vehicles. The principle is shown to yield the flows for all possible 'Riemann problems' arising in a homogeneous highway, so that its application in a simulation is equivalent to the Godunov 'classic' finite difference approximation method. The principle is appealing because its physical basis, unlike purely mathematical formulae, suggests a natural way in which boundary conditions for practical problems may be treated. Perhaps the IT principle will prove useful for solving general problems, e.g. involving multi-commodity networks. This issue deserves more study. As an illustration of this potential the paper shows that an IT simulation of the finite highway problem solved in the companion paper matches rather well the exact solution. Additional tests using other boundary conditions for the same problem also revealed a good match.

Comments

Transportation Research Part B Home Page: http://www.sciencedirect.com/science/journal/01912615