Research on Type Selection and Plan Design of Urban Overpass

The urban road overpass has its own features: (1) Calculated vehicle speed is rather low; (2) The traffic organization is complex; a huge amount of non-motorized vehicles and pedestrians are present; (3) The land use is urgent, the buildings are densely distributed around and there is a network of underground pipelines; (4) The road amplitude is rather wide and section is diversified. Therefore, the type selection and design principles of urban road overpass are different from those of highway overpass: First, the form of overpass has to be compatible with the property and traffic functions of crossed road; the selected category assures safe and smooth traffic and continuous vehicle flow; The form of overpass must adapt to the local environmental conditions; an integrated consideration is made under the condition of meeting the traffic requirements in order to make a reasonable use of typography, practice economy to the project operation expense, coordinate with the environment and realize beautiful profile and stylish structure; Special attention is paid to the integration between nearby and remote profiles before an integrated consideration is made; The main line and ramp are collocated in sequence and an integrated arrangement is made; The category is selected according to the actual conditions and favorable conditions are provided for the project construction. This article integrates with the urban overpass case, elaborates on the demand for urban overpass construction and makes use of category selection of overpass to verify the scientific and reasonable properties of plan design.