地面沉降模型的参数全局敏感性  

Global sensitivity analysis of parameters in land subsidence model

作　　者：罗跃 叶淑君[2] 吴吉春[2] 章艳红 焦珣[3] 王寒梅[3] LUO Yue;YE Shu-jun;WU Ji-chun;ZHANG Yan-hong;JIAO Xun;WANG Han-mei(School of Water Resources and Environmental Engineering,East China University of Technology,Nanchang 330013, China;School of Earth Sciences and Engineering,Nanjing University,Nanjing 210046,China;Key Laboratory of Land Subsidence Monitoring and Prevention,Ministry of Land and Resources,Shanghai Geological Survey, Shanghai 200072,China)

机构地区：[1]东华理工大学水资源与环境工程学院,江西南昌330013 [2]南京大学地球科学与工程学院,江苏南京210046 [3]上海地质调查研究院国土资源部地面沉降监测与防治重点实验室,上海200072

出　　处：《浙江大学学报（工学版）》2018年第10期2007-2013,2034,共8页Journal of Zhejiang University：Engineering Science

基　　金：国土资源部地面沉降监测与防治重点实验室开放基金资助项目(20140012);国家自然科学基金资助项目(41272259;41602258);东华理工大学江西省数字国土重点实验室开放研究基金资助项目(DLLJ201608)

摘　　要：为了提高地面沉降模型(COMPAC模型)参数自动校正(或反演)的效率,降低不确定性,使用Sobol'全局敏感性分析方法,以静态和动态的方式分别计算上海市地面沉降模型中5个参数(弱透水层渗透系数、塑性贮水率、弹性贮水率、前期最低水位和含水层贮水率)的一阶、交互和总敏感度,讨论不同变形阶段和参数区间对敏感度计算结果的影响,得出以下结论. 1)含水层贮水率的敏感度较小,说明该参数对模拟结果的影响有限,该模型不能准确地反演该参数. 2)各参数敏感度在不同变形阶段存在明显的差异,在弹性变形阶段,土层变形量主要受弱透水层弹性贮水率的影响;塑性变形阶段变形量主要受弱透水层塑性贮水率、渗透系数和前期最低水位的影响,说明模型可在弹性变形和塑性变形2个阶段分别校正参数. 3)模型参数的交互敏感度较大,但通过分析观测数据,确定参数的合理区间,可以减小交互敏感度,即减小了"异参同效"性,降低了参数校正或反演的不确定性.Sobol’method was used to conduct a global sensitivity analysis of five parameters in the land subsidence model of Shanghai city in order to reduce the model uncertainty and enhance efficiency of the calibration(or inversion)on land subsidence model.The parameters were as follows:Kv(vertical hydraulic conductivity of the aquitards),Sskv(aquitard nonrecoverable skeletal specific storage),Sske(aquitard recoverable skeletal specific storage),PPmax(initial preconsolidation stress within the aquitards)and Ssk(skeletal specific of the aquifer).Total sensitivity,the first-order sensitivity and interaction sensitivity indexes were calculated on the response variable of mean square error(MSE).Then the impact of the parameter range and time series result simulated by land subsidence model on sensitivity analysis was discussed.1)Ssk shows low sensitivity,which implies its less influence on simulated deformation.Ssk can be fixed at a given value when the model is calibrated or inversed.2)Parameters sensitivity in different deformation phases shows different characteristics:Sske shows the most influence on deformation during elastic deformation phase;Kv,PPmax and Sskv show the most influence on deformation during plastic deformation phase.This implies the parameters in land subsidence model can be calibrated by each of two deformation phases.3)The interaction sensitivity of parameters shows high value.This implies that the model may encounter equifinality when it is calibrated.The possibility of equifinality can be decreased when the range of PPmax is reduced for sensitivity analysis by analyzing the curve of groundwater level and deformation.

关 键 词：全局敏感性分析 动态敏感性分析 地面沉降模型 参数反演 参数校正 

分 类 号：P641[天文地球—地质矿产勘探]