考虑初始含水率非均匀分布及孔隙水重分布的边坡可靠度分析  

Reliability analysis of slope stability considering non-uniform distribution of initial soil water content and pore water redistribution

作　　者：元志镕 蒋水华 常志璐 向晖 刘玉伟 黄劲松[1] YUAN Zhi-rong;JIANG Shui-hua;CHANG Zhi-lu;XIANG Hu;LIU Yu-wei;HUANG Jin-song(School of Infrastructure Engineering,Nanchang University,Nanchang,Jiangxi 330031,China;School of Resources&Environment,Nanchang University,Nanchang,Jiangxi 330031,China;China State Construction Railway Investment&Engineering Group Co.,Ltd.,Beijing 102601,China;Natural Resources Policy Investigation and Evaluation Center of Jiangxi Province,Nanchang,Jiangxi 330045,China)

机构地区：[1]南昌大学工程建设学院,江西南昌330031 [2]南昌大学资源与环境学院,江西南昌330031 [3]中建铁路投资建设集团有限公司,北京102601 [4]江西省自然资源政策调查评估中心,江西南昌330045

出　　处：《岩土力学》2025年第3期1001-1012,共12页Rock and Soil Mechanics

基　　金：国家自然科学基金项目(No.52222905,No.52179103,No.42272326,No.52407241);江西省自然科学基金项目(No.20242BAB24001,No.20232ACB204031,No.20224ACB204019)。

摘　　要：建立合理的降雨入渗分析模型是分析降雨诱发边坡失稳机制及防控滑坡灾害的重要前提。目前Richards方程数值解和Green-Ampt模型常用于边坡降雨入渗分析,然而Richards方程数值解易出现计算不收敛问题,Green-Ampt模型计算精度较低,不能考虑初始含水率非均匀分布和孔隙水重分布过程。在传统Green-Ampt模型基础上,将边坡地层沿深度方向离散为多个空间微元,将降雨事件离散为多个小时段,进而提出边坡降雨入渗分析的时空逼近法,阐明降雨入渗下非均质无限长边坡渗流、稳定及可靠度演化规律。结果表明:与Richards方程数值解相比,提出的时空逼近法是一种计算稳定且精度较高的降雨入渗分析方法,不存在计算不收敛问题。此外,如果不考虑孔隙水重分布过程会低估边坡失效概率和错误估计最危险滑面位置。研究结果可为复杂边坡降雨入渗分析及降雨型浅层滑坡灾害防控提供理论支撑。Establishing a reasonable rainfall infiltration model is crucial for understanding the mechanisms of rainfall-induced slope failures and for preventing and controlling landslide disasters.Currently,numerical solutions to the Richards equation and the Green-Ampt model are commonly employed to analyze rainfall infiltration in slopes.However,numerical solutions to the Richards equation often encounter convergence issues,while the Green-Ampt model suffers from relatively low accuracy and an inability to account for non-uniform initial soil moisture distribution and pore water redistribution.In this study,we propose a spatiotemporal approximation method based on the Green-Ampt model for analyzing rainfall infiltration in slopes.This method involves discretizing the slope stratum into multiple spatial elements along the depth and dividing the rainfall event into multiple time intervals.Using this method,we investigate the changes in seepage,stability,and reliability of heterogeneous infinite slopes under rainfall infiltration.The results show that,compared to numerical solutions of the Richards equation,the proposed method is a robust and accurate approach for analyzing rainfall infiltration,with no convergence issues.Additionally,ignoring the pore water redistribution process can lead to underestimating the probability of slope failure and misidentifying the location of the critical sliding surface.The research outcome can provide theoretical support for rainfall infiltration analysis of complex slopes and prevention and control of rainfall-induced shallow landslide disasters.

关 键 词：边坡可靠度分析 空间变异性 降雨入渗分析 初始含水率 孔隙水重分布 

分 类 号：U213.1[交通运输工程—道路与铁道工程]