Research On Integrated Urban And Regional Travel Demand Analysis Theory And Method

With the development of urban agglomeration and integrative regional economic, and enhancement of urbanization and urban transport motorization, the amount and character of the trip between urban and satellite town have changed very much. Therefore, research on the regional travel demand are still insufficient to meet the need of planning and construction of regional integrated transport system.Regional trip and urban trip are very different, traditional four-step urban travel demand model isn't adapt to analyze regional trip, we should according to the regional travel demand characteristics, research and development relevant regional travel demand model to achieve the accuracy analysis and forecasting of regional travel demand.Based on this, the paper aimed at the travel demand on the main corridor of the region, taking external trip as the linkage of the regional trip and urban trip, presented the framework and technical route of integrated urban and regional travel demand analysis, constructed the model system of external travel demand analysis. The main contents of this paper include the following:1. Through the in-depth analysis and summary of the current problem of urban and regional transport travel demand forecasting research and practice, and the system analysis of the regional trip and urban trip, open out the essence that the flow quality between the center city and the main node in the regional is the external trip of the center city and the main node in the regional, establish the basic idea that the contact media of the regional trip and urban trip is the external trip of the center city and the main node in the regional, based on this, presented the framework and technical route of integrated urban and regional travel demand analysis.2. On the foundation of summarized the experience of travel survey at inland and overseas, expatiated the basic theory and methods of the urban external transport system and external travel behavior survey, and the issues of the split of travel analysis zones and SP survey design have been discussed. Taking Shenzhen external trip survey as an example, explicated the survey design and implementation, and the socio-economic characteristics of Shenzhen's external trip maker, external trip characteristics, and external trip in the city's spatial distribution characteristics are analyzed and summarized.3.This paper studied and improved the existing traditional "four-step method", regional and inter-city travel demand forecasting model, aimed at the actual situation of Shenzhen and the Pearl River Delta region, constructed urban external travel demand model system within the scale of the urban agglomeration, formed an integrated multi-level NL model structure based on MNL models, the model system included the external trip generation model, destination choice model, main mode choice model and access mode choice model, and achieved linkage and feedback of each model through Logsum variable.4. The basic principle, influencing factors, the utility function settings, coefficient calibration and statistical tests of each sub-model were explained in detail and description.Which disaggregate model-based external trip frequency model and destination choice model to predict the generation and distribution of external trip, compared to the original unit generation method and gravity model, they could better reflected the impact of the transportation network, travel impedance and external environmental changes on the trip generation and trip distribution. Due to the short distance of intercity corridor, the time spent on urban traffic and waiting at the two terminals of the city occupies a majority of the whole trip, which has a great impact on traveller's main mode choice, therefore, established combined model of main mode choice and access mode choice, the combined model can solve this problem.5.Taking into account the current demand forecasting problems and the fact that the future development of growing uncertainty and complexity, suggested that we should make decision analysis on travel demand forecasting, analyzed the necessity to make decision analysis of travel demand forecasting and the existing decision problem of travel demand forecasting, withal, put forward a scenario planning method to make decision analysis of travel demand forecasting, and described the specific steps in the scenario planning method used in decision analysis of travel demand forecasting.In conclusion, this paper made comprehensive and in-depth exploration and research on urban external travel survey, external trip characteristics, external travel demand model and decision analysis of travel demand forecasting etc, could provide theoretical and methodological support on regional comprehensive transportation system planning and demand forecasting, urban external transportation system planning and demand forecasting etc, and has strong theoretical and practical value.