Assignment techniques for networks with junction modelling

摘要

The modelling of congested urban road networks has been the subject of ongoing research around the world for some time. A variety of methods have been developed with varying levels of success and accuracy. A fundamental issue has been the trade off between obtaining results that can be interpreted for strategic planning purposes, and the need to represent traffic operations accurately at a local level. Many cities require a flexible modelling tool that is capable of assessing both. Ove Arup & Partners have recently developed and validated an EMME/2 model to assess transport projects for the Auckland City. New Zealand that incorporates datailed representation of junction delay, which draws on previous work undertaken by RO Hill. The research and development of the modelling tool highlighted many improtant modelling issues. This paper discusses the issues related to congested assignment model development and describes an approach to achieve the objectives of city-wide models. Topics discussed include: a. assignment methods; b. stability and convergence; c. appropriate level of detail for citywide models; d. link and tum penalty functions; e. delay functions at signalised junctions.