INTEGRATED REAL-TIME RAMP METERING MODEL FOR NONRECURRENT CONGESTION: FRAMEWORK AND PRELIMINARY RESULTS

An integrated real-time ramp metering model for nonrecurrent freeway congestion among link flows has been developed and tested in this study. The core concept of the proposed algorithm is to capture the dynamic traffic state evolution with a two-segment linear flow-density model. To be implemented in real time, an effective solution algorithm has been proposed for determining the time-varying metering rates. The entire algorithm has also been integrated with INTRAS, the most well-known freeway simulation model, for conducting simulation experiments. Preliminary research results indicate that the proposed integrated control model is promising because its effectiveness increases with the severity of accidents and the level of congestion. The model execution time is also sufficiently short for potential real-time operations.