Research On The Functional Zoning Of Engineering Geological Environment In Jinjiang Based On GIS

Engineering geological conditions are the important influencing factors of urban planning and construction.In recent years,the unreasonable planning and development of city have caused many environmental engineering problems.To recarch the harmonious development of the "earth-human",it is urgent that the division of engineering geological environmental functional area should be used to guide the development of urban construction projects.The influencing factors of engineering geological environmental functional zones are complex.This paper analyses the geological environmental datas of the study area,such as topography and geomorphology,geotechnical types and mechanical properties,the characteristics of geological structures,the characteristics of geological disasters,groundwater and so on.Establish the evaluation index system of engineering geological environmental functional division;research the quantitative description method of evaluation index;build the appraisal model of engineering geological environmental functional regionalization.Using the GIS space analysis function,realize engineering geological environmental functional division in Jinjiang city,which provides decision-making support for urban planning and construction programs of related departments,and provides a reference for engineering geological environmental functional zones of other coastal cities of taiwan straits west bank economic zone.The main research contents are as follows:(1)Study of engineering geological environmental functional zoning evaluation index system.According to the analysis of the engineering geological conditions in Jinjiang,such as topography and geomorphology,geotechnical types and mechanical properties,the characteristics of geological structures,the characteristics of geological disasters,groundwater and so on,this paper selects the main factors that influence the engineering geological environmental functional regionalization;establish a suitable evaluation index system of the study area.Index system is composed of five level indicators(for the characteristics of geotechnic,the fracture structure,the characteristics of geological disasters,the characteristics of undergroundwater and topography and geomorphology)and twelve secondary indexes(for geotechnical types,geotechnical structure,fracture property,fracture activity,landslides hazard,avalanche disaster,embedded depth of groundwater,groundwater pollution degree,terrain slope and the geomorphic types respectively).(2)Research on the index weighting method and the comprehensive evaluation model.Use the analytic hierarchy process to determine subjective weights of each indicator.Use the entropy method to calculate the objective weight of every index.Finally,make a comprehensive based on the principle of minimum information entropy and obtain the combination weights of each index.The scoring system was made to acquire quantitative attribute information through expert evaluating method.According to the scoring system and the combination weights,the additive synthesis of the engineering geological features was used to construct the comprehensive evaluation model of engineering geological environmental functional zoning in Jinjiang city,that achieve an index conversion from qualitaty to quantitaty.(3)Research on engineering geological environment functional regionalization based on GIS.According to the comprehensive evaluation model,use the spatial analysis function of GIS to make grid subdivisions of all index features in Jinjiang area.Calculate unit composite scores of each subdivision by the spatial superposition function.Then,realize engineering geological environmental functional division of Jinjiang city,and displays the divisions.