Urban freeway plays a key role in the urban transportation system and also takes a lot of share in the urban traffic generated in the big city. However, most of the urban freeways are experiencing the transportation problems including severe traffic congestion regardless of the peak periods because the new travel demands keep increasing. Thus, the purpose of this study is to investigate the traffic characteristics, analyze the relationships between the traffic characteristics and finally construct the speed predictive models on the merge sections in the congested urban freeway interchange with the speed surveillance devices installed in city of Busan.
From the analyses of traffic characteristics, and construction and verification for the delay predictive models on the merge sections of the urban freeway interchange under the study, the following conclusions were drawn i) Traffic flow showed a big difference depending on the time periods in the urban freeway interchange. Particularly more traffic were concentrated on the urban freeway interchange in the daytime period when compared with the nighttime period.
ii) Traffic flow also showed a quite difference depending on the travel directions in the urban freeway interchange. Particularly more traffic were concentrated on the urban freeway interchange in the inbound direction when compared with the outbound direction.
iv) The Urban freeway traffic management system(UFTMS) measures like the variable message sign(VMS), ramp metering system, or both were shown to be more effective on the inbound entrance ramp in the morning rush hour.