基于DE-MCMC方法的滑坡堆积体土壤水力参数反演研究  

Inverse Estimation of Soil Hydraulic Parameters in a Landslide Deposite Using DE-MCMC Method

作　　者：蔡忠周 严海文 李美骏 邵伟 杨宗佶[4] CAI Zhongzhou;YAN Haiwen;LI Meijun;SHAO Wei;YANG Zongji(School of Hydrology and Water Resources Engineering,Nanjing University of Information Science and Technolo-gy,Nanjing 210044,China;Key Laboratory of Hydrometeorological Disaster Mechanism and Early Warning,Ministry of Water Resources,Nanjing 210044,China;Qinghai Meteorological Disaster Prevention TechnologyCenter,Xining 810000,China;Chengdu Institute of Mountain Hazards and Environment,Ministry of Water Resources,Chinese Academy of Sciences,Chengdu 610041,China)

机构地区：[1]南京信息工程大学水文与水资源工程学院,江苏南京210044 [2]水利部水文气象灾害机理与预警重点实验室,江苏南京210044 [3]青海省气象灾害防御技术中心,青海西宁810000 [4]中国科学院水利部成都山地灾害与环境研究所,四川成都610041

出　　处：《灾害学》2024年第3期48-53,共6页Journal of Catastrophology

基　　金：青海省科技厅基础研究项目“青藏高原优先流影响下的滑坡触发机理及降雨滑坡集合预警研究—以玉树称多地区为例”(2023-ZJ-705);国家自然科学基金青年科学基金(41807286);国家自然科学基金面上项目(41877158)。

摘　　要：极端降雨条件下,入渗可急剧增大滑坡体中软弱结构面上的土壤含水量和孔隙水压力,是触发滑坡的重要因素。因此,土壤水动力模拟是滑坡预警系统的核心,其模拟结果的准确与否取决于土壤渗透特性的参数化。该文以汶川地震扰动区的银洞子滑坡堆积体为例,以土壤含水量野外观测数据为基础,基于Richards方程构建入渗模型,利用自适应差分演化算法的马尔科夫链蒙特卡罗方法(Differential Evolution Markov chain Monte Carlo,简称DE-MCMC)反演van Genuchten土壤水力参数。通过比较土壤含水量的模拟值与实测值的拟合程度,评估DEMCMC算法在土壤水动力模拟中的适用性。结果表明,基于DE-MCMC算法反演的后验参数极大降低了先验参数分布的不确定性,并显著提升土壤含水量的模拟精度。将DE-MCMC方法应用于滑坡水文,可有效率定土壤渗透特性参数,为降雨型滑坡预警提供更为可靠的土壤水动力模拟结果。Under extreme rainfall conditions,infiltration can dramatically increase the soil water content and pore water pressure on the weak structural surface of the landslide,which is an important factor to trigger land⁃slide.Therefore,soil hydrodynamic simulation is the core of landslide warning system,and the accuracy of simu⁃lation results depends on the parameterization of soil permeability characteristics.Taking Yindongzi landslide de⁃posit in Wenchuan earthquake disturbance area as an example,an infiltration model based on Richards equation according to soil water content field observation data is built.Markov Chain Monte Carlo(DE-MCMC)method is used to retrieve van Genuchten soil hydraulic parameters.The applicability of DE-MCMC algorithm is evaluated by comparing the simulated and measured soil water content.The results show that the posterior parameter inversion based on DE-MCMC algorithm greatly reduces the uncertainty of the prior parameter distribution and significantly improves the simulation accuracy of soil water content.The application of DE-MCMC method to landslide hydrolo⁃gy can effectively determine soil permeability characteristics and provide more reliable soil hydrodynamic simula⁃tion results for rainfall landslide warning.

关 键 词：滑坡堆积体 土壤水分特征曲线 参数反演 van Genuchten模型 DE-MCMC算法 RICHARDS方程 

分 类 号：X43[环境科学与工程—灾害防治] X915.5