Abstract:To alleviate the traffic congestion problems on urban freeways, a method is proposed to determine the control priorities of coordinated onramps metering of urban freeways using the risk assessment techniques and the QHM(quantitative hierarchical model) to classify a freeway corridor into subsections. The priority matrix is constituted by the density ratio of the current status of the subsections over the critical status and is used for the determination of control priorities of multiramps of freeway corridors. It can ensure the smoothness, fairness and consistency among subsections. Finally, the reliability and the feasibility of the proposed model is verified by the case using the Vissim simulation.