Environmental Assessment of Urban Rail Transit Station Area Based on TOD Mode —— A Case Study of Ranjiaba Station in Chongqing

The concept of transit-oriented development (TOD) was first put forward in the 1980s. As one of the most successful sustainable development models of cities and transportation, TOD is an important way to realize the integration of traffic and land use,promote land use intensification and diversification, and form green traffic leading urban development . As China's national economic development enters the new normal, urban development has entered the transformation stage of high quality development from the past extensive expansion, and the TOD has become an important grasp to realize the transformation of urban high quality development. As an important hub with high development intensity, large population agglomeration and extremely complex transportation in urban rail transit system, rail transit station area can significantly improve the overall operation efficiency of rail system,more effectively promote the comprehensive development and utilization of site regional resources, which has a pivotal position.However, because the construction of urban rail transit system lags behind the development of land use, the site area often lacks the reserved space to match it, which leads to the limited development of the current rail station area. It is difficult to further promote its follow-up high-quality development.In addition, the highly complex ecological and construction conditions of mountain cities and the relatively lack of targeted research in China at present, the vigorous development of mountain urban rail transit system in the future is facing severe challenges. Based on the evaluation tools of geographic information system (GIS), this paper takes the rail transit station site,Ranjiaba station area in the main urban area of Chongqing, as an example, combs the characteristics of land use, spatial connection and functional use material elements in the surrounding block space, and delimits the research scope suitable for the mountain city site area. After that, according to the hierarchical analysis method, the TOD environmental evaluation index system which affects the coordinated development of land use and transportation system in rail transfer station area is constructed from two aspects. The comprehensive development results of Ranjiaba rail station area are analyzed by visualization and quantification, and the environmental characteristics and weak links are summarized. Based on this, this paper puts forward some suggestions on land and traffic optimization which are more suitable for the current TOD mode, in order to provide a certain reference for the integration and utilization of space resources in the surrounding blocks of urban rail transit station.