基于有限区间云模型的地面塌陷危险性评价

Risk Assessment of Ground Collapse Based on Finite Interval Cloud Model

随着城市化进程的加快,城市地面塌陷发生的频率也越来越高。对城市各区域开展地面塌陷危险性评价就显得尤为重要。为提高评价结果的合理性,提出基于有限区间云模型和改进层次分析法的地面塌陷危险性评价方法。以深圳市福田区为例,选取月降雨量、路基土回填程度、交通荷载等9个指标建立地面塌陷危险性评价指标体系,并引入有限区间云模型方法计算各评价因子隶属于不同分类等级的云特征参数,通过正向有限区间云发生器生成云滴图,得到评价因子隶属于不同等级的确定度,实现了不可量化变量与指标值之间的不确定性和随机性映射;在此基础上,结合改进的层次分析法计算指标权重,得到评价样本的综合确定度,并按照最大隶属度原则确定地面塌陷危险性等级。该评价方法综合考虑了地面塌陷危险性等级边界的模糊性,最大程度地保证了评价结果的合理性,可为城市地面塌陷的防治工作提供一定的指导。

With the acceleration of urbanization,the frequency of urban ground subsidence is also increasing.Therefore,it is very important to carry out the risk assessment of ground subsidence in various urban areas.In order to improve the rationality of the evaluation results,this paper presents the risk assessment method of ground collapse,which is based on the finite interval cloud model and improved analytic hierarchy process.Taking Futian District of Shenzhen City as an example,the paper selects nine indexes including monthly rainfall,subgrade soil backfill degree and traffic load to establish the evaluation index system.The paper obtains the cloud characteristic parameters of each evaluation factor belonging to different classification levels through the finite interval cloud model,and applies the forward finite interval cloud generator to generating cloud drop graphs of the indexes.Further,the paper obtains the certainty degrees of the evaluation factors belonging to different levels,which provides the mapping of uncertainty and randomness between the semantic variables and the index values.On this basis,combined with the index weight calculated by the improved AHP,the paper obtains the comprehensive determination degree of evaluation samples,and determines the risk level of ground collapse according to the principle of maximum membership degree.The evaluation method comprehensively considers the fuzziness of the risk level boundary of ground collapse,which ensures the rationality of the evaluation results to the greatest extent,and provides certain guiding significance for the prevention and control of ground subsidence.