| With the rapid development of economy, vehicle registrations are growing fast and traveltimes are generally high and increasing. Especially in large cities, oversaturated trafficcongestion has become the norm. Oversaturated traffic congestion and the attendant issuessuch as environmental pollution and energy shortage have become the major problems ofurban development and living standards.On the basis of analysis of research and development status of the traffic demandmanagement measures, the perimeter active control and congestion pricing that directlymanage and control oversaturated traffic congestion are selected as the main study measures.In order to overcome the shortages of current methods, some creative and useful methods andalgoritms are proposed. Main research contents and results of this dissertation are asfollowing:(1) Based on requirements of oversaturated perimeter control method, the lane-groupbased macroscopic traffic flow formulations is improved, lane-group based oversaturatedintersection macroscopic traffic flow formulations and branch macroscopic traffic flowformulations are established. The formulations could model the dynamic interactions of trafficflows when queues spillback occurs and the entering and exiting traffic dynamic of brancheswell. The improved lane-based macroscopic traffic flow formulations could satisfy the needsof perimeter active control in time and accuracy.(2) Perimeter active control strategy of oversaturated area is proposed. Traffic volumcleaning algorithm is designed to gain real traffic demand and identify the key intersectionsthat cause regional traffic congestion. Then, the green splits are optimized, actively control thetraffic entering the oversaturated areas and hold a portion of traffic outside, avoid theoversaturated traffic congestion to occur. The single-layer perimeter active control strategyunder given perimeter and the multi-layer perimeter active control strategy under dynamicdetermined perimeters are put forward respectively, which provides a new way and thinkingfor oversaturated traffic control.(3) Based on static perimeter active control, the dynamic signal coordination model foroversaturated aterials is proposed. This model takes the main traffic flow direction of theatertial as the coordinate direction, optimizes the green splits by perimeter active controlstrategy and dynamic optimizes the cycles to make sure that offsets of all neighboringintersections satisfy the ideal offsets, avoids the queue spillback and the lose of green time,maximizes the intersections' capacity and minimizes the network delays. (4) The key intersections based division method of oversaturated coorditnaed controlsubareas is proposed. By comprehensive analysis of the influences factors, the traffic volumeaccumulated paths from oversaturated area perimeter to the key intersections are indentified.Each path is considered as a control subarea and subareas having a common key intersectioncompose a subarea group. The divison method breaks through the traditional concept ofcoordinated control subareas division and proposes a new way for the division ofoversaturated coordinated control subareas.(5) As area-based congestion pricing could well restrict cars running into city center andpark and ride (P&R) could encourage public transport while doesn't affect convenience ofdriving, two measures are combined to relieve traffic congestion problem in urban area.Combined area-based congestion pricing and P&R network equilibrium conditions isproposed and combined area-based congestion pricing and P&R network equilibrium modelis established. Further, a modified Gini coefficient is proposed to measure the social andspatial equity impact. The combined measure could increase the social and spacial equity andenhance the operability and social recognition.(6) Uniformly Pareto-improving congestion pricing and revenue refunding schemes inbimodal (automobile and bus) transportation networks is proposed. Bimodal multi-classnetwork equilibrium model is formulated, and the exsiting condition that uniformlyPareto-improving congestion pricing and revenue refunding scheme exist if and only if thetotal travel costs of people who have been driving cars before pricing is reduced is proposed.Further, a bi-level programming model and solution algorithm are proposed. The schemecould relieve traffic congestion while automobile-insistent users and shifting-automobile usersare equally better off regardless of their value of time (VOT) and origin-destination (OD)pairs and would be easily accepted by the public. However, related with the level of currentcongestion and transit service, the ideal scheme doesn't always exist.(7) At last, the oversaturated areas traffic management and control measures proposedare evaluated from the scope of application, implementation effectiveness, implementationcosts and equity, providing the gudie for traffic managers to select the suitable measure.Overall, this dissertation provides a set of oversaturated traffic managent and controlmeasures for traffic managers. |
