Evaluation Of Susceptibility To Karst Collapse And Sensitivity Analysis Of Influencing Factors In Wuhan

Located in the middle of China,Wuhan is located at the east of Jianghan Plain and at the junction of the Yangtze River and the Han River.It is a large and important city in the middle of China.The Karst development environment in Wuhan are very complex.In the past three decades,with the continuous expansion of urban areas and the increase of major urban construction projects,karst collapses in Wuhan have occurred from time to time.Karst collapse has been the most serious geological disaster of Wuhan.In this context,the 1:50000 karst collapse investigation project in Wuhan was carried out.This article relied on this project to evaluate the susceptibility of karst collapse in Wuhan City and we hope to contribute to the development of Wuhan.The purpose of this article is to use the analytic hierarchy process and the weighted average composite index method to evaluate the survey area for susceptibility,and then use the single factor analysis method to analyze the sensitivity of the impact factors.First,based on summarizing the research status of susceptibility evaluation and sensitivity analysis of karst collapse at home and abroad,the data required for the article were collected and analyzed,and the temporal and spatial distribution of historical karst collapse events in the study area was analyzed and summarized,As same as the geographical and geography overview.Then,by analyzing its influencing factors,combining with the actual situation of local collapse in Wuhan City and seeking expert advice,we select the required evaluation indicators,construct its hierarchical structure model,calculate the weight of each indicator using the square root method,and finally construct its Efforts were made to evaluate the model,and then combined with GIS software,the single-factor maps were superimposed and revised according to the evaluation model.Finally,the susceptibility map was obtained and the entire evaluation was completed.In the final zone,1.8 to 3 were designated as high,1.5 to 1.8 were designated as middle,0 to 1.5were designated as low,and 0 was designated as zero.According to the results of the analysis of the susceptibility of the survey area,the areas of high,medium,and low-degree regions are 149.62km~2,231.03km~2,and384.35km~2,respectively.Their respective percentages in the survey area are5.61%,8.67%,14.42%.According to the sensitivity analysis of the influencing factors,the order of sensitivity of the five factors from the largest to the smallest is,From high to low:(1)High-susceptibility areas:Quaternary structure,karst collapse density,Quaternary water,degree of karst development,and Quaternary thickness.(2)middle-susceptibity areas:Quaternary thickness,Quaternary structure,degree of karst development,Quaternary water,karst collapse density.(3)low-susceptibility areas:Quaternary thickness,Quaternary water,Quaternary structure,karst collapse density,degree of karst development.