A Study on the Average Travel Speed on Interrupted Flow Multi-Lane Highways

Intersections, whether signalized, STOP controlled, or YIELD controlled form some of the main features that define interrupted flow facilities. In addition to the imposition to stop that comes with the red indication of traffic signals, other settings such as the cycle length and offsets have a great impact on the amount of delay encountered, and therefore the average travel speed. Improper settings are likely to bring about a reduction in the performance of the highway, and therefore it is important to forecast their potential impacts on the planned highways’ performance. In this study, we examine the variation in the average travel speed along a hypothesized two-lane highway by changing the segment length, density of signalized intersections, cycle length, and offset settings. Results showed that average travel speed reduced with increased signalized intersection density, and that the network layout also had a significant impact on the travel speed. Furthermore, it was shown that based on the link length and the free flow travel time, the choice of cycle length and offset settings has a very significant impact on the travel speed.