The Planning Study On Urban Underground Expressway Network

Urban underground road network construction can alleviate current situation and tendency of traffic congestion in urban central district, save land resources at maximum, and also can make the urban construction keep open space, plenty of sunshine, fresh air, beautiful landscape, and large-area green land and water, providing the living and working conditions for the residents without traffic environment influences.At present, urban underground road systems which have be finished or are under planning and construction are many at home and abroad, but without systematic research on the planning process. Planning construction of urban underground road system is qualitatively different from it of ground road system planning, mainly reflecting that urban underground road system owns the basic characteristics of underground project,and the influences of topography and geomorphology, geological condition are very important. So it is not only from the path of planning ideas to discuss planning and construction of urban underground expressway network. Combining with chongqing torch-plan projects "key technology research on construction of underground fast road network in Chongqing downtown areas ", the urban underground espressway network planning and construction were studied, firstly beginning from characteristics of underground engineering, plan elements of "the model of entrance location "and "underground overpass hub"etc were explored; by analyzing the urban road planning methods, rail transportation planning thought, multi-modules delaminating point, line and plane element methods were put forward to satisfy the urban underground road network planning; finally, schemes evaluation, comparison and selection and risk analysis of the urban underground fast road network were discussed, etc.The main innovation points and work of the paper are as follows: Combined with the characteristics of underground engineering, principles meeting urban underground fast road network planning were summarized and discussed, and planning content needing to be considered was summarized; For satisfying urban road network, the location model of entrance and exit was built, and the feasibility of the model was tested and verified through examples; It expounded operation process of multi-modules delaminating point, line and plane element method in urban underground expressway network planning, and discussed evaluation method and risk grading assessment of the planning scheme.