The Research And Application Of CAD System About Railway Routing Selction Based On GIS

According to the modern railway location design development's tendency and the "3S" technical wide application situation, applies GIS in the railway route selection design is one of key and hot spots current research, use the GIS formidable spatial analysis and decision power, the multi-dimensional and level expression and the three dimensional visualization unique superiority and so on, according to the railroad of CAD choose wire system tapping present need to completely promote, but use the surname obstruction space's most short-circuit diameter theory wire ways scheme turn to excellent have more good of applied foreground.Google Earth is a section of application widespread three dimensional visualization Earth software in the current GIS applicat, it is has GIS information arrangement, satellite phantom and aerial photograph, three dimensional terrain pattern on an Earth's three-dimensional model, has a series of character can Satisfy the requirement that the railroad chooses a wire design, so it has important realistic meaning to choose the search of wire design according to the GIS progress railroad.Aim at some scarcity that current use railroad chooses the wire CAD system existence, this text with Microsoft Visual Studio 2010 for develop platen, with AutoCAD Civil 3D 2011 for a paint platen to CAD and GIS, at the same time use Earth and SRTM as a GIS data source, adopt C# language forming GIS and CAD double tapping mode, on the originally all foundation carried out the organic wedge bonding and advantage complement of GIS and CAD thus. Through apply GIS at railroad chooses wire to design each aspects completely that effectively compensate current software's defects, at the same time expanded function application, thus it is promote the technique leave that chooses the railroad wire design obviously.In this paper separately has made a detailed analysis and comparison to CAD and the GIS's re-development technology, and determines quite reasonably and reality feasible development program according to the realistic situation, to guaranteed designs the function may program realizes. Through careful analysis the origin Google Earth data and its precision, thus infers the feasible method that the Beijing 1954 place coordinates and WGS-84 geodetic coordinates used in railway location can inter conversion, simultaneously selected the scene experiment's method to confirm the data conversion precision and the reliability, then determined the feasibility and application scope that the GIS data used in the railway location design.Finally, this paper detailed introduction and analysis the key technologies which used in overall system's performance, overall introduction realized based on the GIS railway location design system's functional design and the concrete program, had exhibit system's surface and the major function establishment, how to realize three-dimensional space has carried on the plane route selection design, the ground elevation data extraction and the land line paints, GIS functional modules and so on resources downloading and use, simultaneously has make the part demonstration to line's three dimensional effect, finally use three dragon railroad's in Fujian south feasibility study for example specifically explain the system's application and further improved way and method, therefore has useful value.