In order to supplement your knowledge about the various concepts within Traffic Flow Theory, and in order to give you a glimpse of how these various topics are discussed in the professional environment, we have included selected excerpts from professional design aids. The Transportation Research Board maintains an Internet website to provide information on all facets of the transportation industry. The professional practice material in this module is excerpted from TRB’s updated Special Report on Traffic Flow Theory, which is published on their website.

Traffic Flow Parameters
Speed-Flow-Density Relationships
Greenshields' Model
Shock Waves and Continuum Flow Models
Queuing Theory