The Establishment Of A Digital Elevation Model And Its Earthwork Calculation Application

Be in the past few years, research and application being related to "digital globe" have been paid close attention to broadly within the whole world range. The digital elevation models also develop rapidly, which is important prop up one of technology of "digital globe" .Now, DEM had broad application at surveying, remote sensing, agriculture and forest planning, urban planning, construction and water conservancy project, earth analysis and GIS and so on. The thesis start from reality needs and mainly commented that constructing model principle and method of DEM by the triangulated irregular network structure. And also, by this algorithm, has construct the constrained delaunay triangulation which has constraint condition. Finally, the thesis mainly studies the application of DEM at the aspect of calculation of earthwork.At first, the thesis discuss the basic concept and characteristic of DEM and analyse the obtained data of DEM by reality application of DEM. The thesis studies the method of constructing the DEM and also calculation of earthwork, by the fabricative digital model. When the thesis is discussing, the thesis bring forward some new methods, as I compared and analysed some arithmetics of DEM and calculation of earthwork. The new realization of arithmetic can form triangulation network more rapid and high accuracy. By this new arithmetic, you can gain more appropriate data.The thesis studies deeply at theory design and method study, as it is paid great attention to application of DEM and calculation of earthwork. Study content and achievement mainly as follows:①The thesis realize compositive arithmetic of constructing holistically three-dimensional landform model, by the triangulation network theoretics. As recollected and analysed some classical arithmetic, I ameliorate point by point insertion algorithm and make it unite with divide and conquer delaunay triangulation algorithm, which is become a compositive algorithm which has excellence of constructing rapidly and using small space. In the process of realization, I put forward the gridding compartmentalizing of equal distribution data point, fast locating point in triangle, simple spatial circumcircle examination method. Through above process improvement, enables the DTIN algorithm which designs to establish the speed of net to be quicker and algorithm more stable.②By constrained delaunay triangulation network and DTIN arithmetic, I bring forward the dynamic algorithm of constructing CDT. After forming CDT, you can dispose long and narrow triangle which is at the borderline of CDT , when you utilized an angle and the topologic information of triangulation network. By this, the precision of constructing DEM triangulation network will be advanced.③Using formed high precision CDT and combining the dividing piece algorithm, the calculation precision of calculation of earthwork is improved greatly. At last, the arithmetic realize automation resolving of the borderline of slope earthwork and calculation of earthwork.