Analyzing roadway work zone effects on vehicular flow in a freeway ring

Roadway work zone forms as a result of traffic accidents or road maintenance. In this paper, to analyze roadway work zone effects on vehicular flow in a freeway ring, a macroscopic multi-lane traffic model is proposed, the model describes the mandatory net lane-changing rate just upstream the roadway work zone with a random number model based on golden section analysis, and the net-changing rate in normal road segment with a lane-changing time model. Assuming that the free flow speeds on lanes I-III are 120, 100 and 90km/h, respectively, with a numerical method of third-order accuracy, the model equations are solved numerically to simulate vehicular flows in a three-lane freeway ring with a roadway work zone with a total length of 160m and lane III completely banned. Numerical results show that the roadway work zone generates traffic shock when initial density normalized by jam density is around 0.18. While the ramp flows have little effect on mean travel time through the freeway ring road with a total length of 100km, but can cause observable deviation of the root mean square value of travel time.