The investigation of an alternative interpretation of the speed-flow relationship for UK motorways

Empirical studies completed in the past half-dozen years in North America have led to a different perspective on the shape of the speed-flow curve. The new curve stems from a recognition that data from three different types of freeway conditions should be kept separate during analysis. This paper addresses the question of whether there are U.K. motorway data that would contradict the proposed new curve shape given the recognition about three types of data mentioned above. The underlying question is whether U.K. motorway traffic behaves fundamentally differently from North American traffic.