Research On The Application Of GIS-based Expression Of Bad Geological Bodies And Route Selection

Modern route selection is becoming more and more dependent on information technology,and it is high time for integration of modern survey technology such as RS,GIS and GPS to gradually realize the transformation from delivery of drawings to delivery of models.How to optimize the route selection scheme in multi-dimensional environment based on the concept of geological route selection remains a technical problem in the transformation.And how to choose a railway line that meets the demands of modern railway is an important task for route selecting engineers.Nowadays,railway calls for high speed,comfort and large carrying capacity,therefore,choosing such a line is an urgent need for the development of modern railway.The goal of geological route selection is to make the best of terrain and geological conditions,to seek a scheme that disturbs the terrain least,and to minimize the remediation and transformation of unfavorable geological sites.Due to the concealment of all kinds of unfavorable geological conditions,the spatial analysis of geological factors becomes the main difficulty in the comparison and selection of route schemes.Sometimes even leads to missing of optimization schemes.Geological data of railway engineering have the characteristics of multi-source,multi-category,multi-quantity,multi-dimension and multi-subject etc.There are also great differences in accuracy,resolution,quantity and quality of various geological data.To guarantee the validity,accuracy and consistency of the information,integration of technical data such as GIS,RS and drilling data is needed to express the whole information,and multi-objective evaluation method of route scheme optimization needs to be combined to meet the demands of three-dimensional and modeling route selection.Therefore,the thesis mainly completes the following work:(1)Interpretation Method of Unfavorable Geology based on Remote SensingThe unfavorable geological phenomena in the area through which the line passes have composite property of plane and elevation.For the landslide,collapse and debris flow in large strip areas,the bad geological phenomena with typical plane regional characteristics such as wind and sand areas can be obtained by remote sensing interpretation method.Simultaneously,combined with the terrain analysis of the strip area,the unified expression of line topography and bad geology based on GIS and RS was realized.(2)3D Geological Body Modeling Method based on GISBased on the existing 3D terrain information,the surface model of 3D geological body was constructed.The method of constructing layered TIN based on discrete strata data was studied according to the drilling data,with the help of the 3D modeling tool in ArcScene.Three-dimensional entity representation of multi-layer geological bodies based on drilling data was also completed,which can be applied in route selection and poor geological entity modeling method.(3)Optimal Selection Method of Plane Line in Unfavorable Geological AreasAiming at the route scheme design and comparison under complex geological conditions,this paper studies the effective expression and extraction of the unfavorable geological characteristics of the route using the functions of data management,spatial analysis and decision-making of GIS,and realizes the extraction of unfavorable geological phenomena in different route areas.An analytic hierarchy process model for auxiliary decision-making of railway in unfavorable geological regions was established,combined with concrete examples,the optimal selection schemes for unfavorable geological regions was realized based on GIS.(4)Design of Integrated Line selection of plane and elevation based on GISGolmud-Korla railway sandy area was taken as an example to analyze the region with unfavorable geology phenomena and its attribute expressing method,and corresponding route selection scheme was designed with the completion of scheme comparison from geological line selection.The method of constructing spatial model of landslide entity based on 3D terrain was then studied taking a newly built railway that travels through landslide area as an example,and different schemes such as detouring,traversing and underpass were designed on the completed entity model,the transformation from original plane detouring method to three-dimensional route selection was realized with the optimal route design scheme obtained after comparison and selection.