Evaluation Of The Suitability Of Underground Space Development In Kunming City Based On Geological Environmental Impact Analysis

With the rapid development of urbanization,there are many urban diseases in large and medium-sized cities in China,such as rapid population expansion,shortage of land resources,traffic congestion,and increasingly acute contradiction between people and land.The development of underground space can increase urban capacity,alleviate traffic congestion,optimize urban spatial structure,and enhance the ability of disaster prevention and mitigation,which is the expansion and extension of China’s land resources.underground space development is an important research field.Geological conditions are the basis for underground space development.In mountainous plateau areas in particular,developing underground spaces requires detailed analysis and appraisal.Because there are many karst and soft soil silt in this area,the geological situation is complex.In order to evaluate the geological environment suitability of underground space development in Kunming City,this paper studies the method and model of the suitability evaluation of underground space development,uses the basic principle and framework of analytic hierarchy process(AHP),introduces the index scale principle,and improves the Saaty scale analytic hierarchy process.Herein,index scale analytic hierarchy process was used to analyze the geological conditions of a plateau.An evaluation system suitable for Kunming,China,was proposed and its index weight was determined.An evaluation model was established using mathematical principles,including multi-objective linear weighting.Meanwhile,geological suitability evaluation of Kunming urban planning area was conducted using GIS,and the evaluation results was statistically analyzed.According to the evaluation,underground space of Kunming urban planning area regarded as suitable,medium suitable,unsuitable,and forbidden for development and construction,accounts for 37.81%,20.38%,17.61%,and 24.2% of its total area,respectively.Among these,soft soil and karst are primary disqualifying influences,followed by groundwater and geological fault zones.The results reveal that the plateau area has more underground space to be exploited.However,there are areas where construction should be controlled more strictly,such as those adjacent to geological fault zones.With this study,the distribution map of geological environment suitability evaluation results of underground space development in Kunming city was obtained,which provides some reference for urban planning and development in Kunming city.At the same time,in the process of research and application of the evaluation method,the superiority of the index scale analytic hierarchy process method was demonstrated,the vector unit rasterization method based on quadtree and parcel attributes was proposed,and their advantages and disadvantages were analyzed.It also puts forward the evaluation system of plateau cities and the consideration criteria of indicators,which has a certain reference significance for the classification and grading of indicators of plateau cities.