Method of constructing fine discrete road grid in urban drainage simulation system

The invention relates to a method of constructing a fine discrete road grid in an urban drainage simulation system and belongs to the cross field of municipal engineering information technology, database technology and geologic information system technology. From the demand on construction of a waterlogging simulation model, under the restraint conditions in road design specifications and on the basis of conventional map measured elevation points, the number and positions of interpolation points are optimized under the drainage simulation system platform by the fitting method of local elevation change curves of cross-longitudinal road section and by road characteristic terrain vector layers according to mathematical model interpolation encryption plane and elevation information of physical road tomography; accordingly, a fine discrete road elevation grid unit is constructed, true tomographic road features are expressed quickly and economically, the demand on precise simulation of waterlogging models is met, especially the dredging and resisting actions of road micro-tomographic features upon waterflow can be correctly expressed, and the method is significant to promotion and application of the drainage simulation technology.