Failure of Generally Accepted Classical Traffic Flow Theories

Abstract

Traffic researchers have developed a huge number of traffic theories for optimization and control of traffic and transportation networks. In particular, to generally accepted fundamentals and methodologies of traffic and transportation theory belong to the Lighthill-Whitham-Richards (LWR) model and the General Motors (GM) model class. These classical theories explain many real traffic flow phenomena. In this Chapter, we show that although these classical traffic flow models exhibit many important achievements, the classical models are inconsistent with the empirical nucleation nature of traffic breakdown at highway bottlenecks. Because the classical models and theories have failed in the explanation of the empirical fundamental of transportation science, the use of the classical approaches for a study of the reliability of applications of intelligent transportation systems (ITS) leads usually to invalid conclusions for real traffic. Moreover, ITS based on these classical traffic flow theories and models cannot also be used for reliable traffic control and dynamic optimization of traffic and transportation networks.