摘要
降雨诱发滑坡是世界上最普遍的地质灾害,而关于降雨入渗对边坡的可靠度分析,优势入渗的影响被长期忽视。使用Comsol Multiphysics对降雨条件下优势入渗做数值求解,利用无限边坡模型计算边坡安全系数;并应用改进Cholesky分解法生成空间相关随机场,使用蒙特卡洛方法分析降雨过程中边坡的可靠度。结合确定性与可靠度计算对比均质入渗与优势入渗在降雨过程中边坡安全性变化:(1)降雨强度较低时,优势入渗安全性较好,而降雨强度较高时,均质入渗更稳定;(2)均质入渗中参数空间变异性是边坡失稳破坏的关键因素,而优势入渗的边坡失稳则由湿润峰快速推进所导致;(3)针对优势入渗模型研究,发现基质域与优势域水力交换强度较大时边坡有更大概率失稳,而较小的水力交换强度可能影响边坡底部的失稳破坏。
Rainfall-induced landslides are the most common geological hazard in the world,and the effect of preferential flow infiltration has been neglected for a long time regarding the slope reliability analysis under rainfall infiltration.The preferential infiltration under rainfall conditions is solved numerically by Comsol Multiphysics,and the slope factor of safety is calculated using an infinite slope model.An improved Cholesky decomposition method is applied to generate spatially correlated random fields,and the slope reliability during rainfall is analyzed using the Monte Carlo method.Combining the deterministic and reliability results to compare the variation of slope factor of safety between the homogeneous infiltration and the preferential infiltration during rainfall,it can be found that:(1) the preferential infiltration model is safer when the rainfall intensity is low,while the homogeneous infiltration is more stable at higher rainfall intensity;(2) the spatial variability of infiltration parameters is the crucial factor of slope failure in homogeneous infiltration,while the slope instability of preferential infiltration is mainly caused by the rapid advance of the wetting front;(3) for the study of preferential infiltration model,the slope has a higher probability of failure when the hydraulic exchange intensity between the matrix domain and the preferential domain,while smaller hydraulic exchange intensity may affect the slope failure at the bottom.
作者
姚云琦
曾润强
马建花
孟祥沛
王鸿
张宗林
孟兴民
YAO Yun-qi;ZENG Run-qiang;MA Jian-hua;MENG Xiang-pei;WANG Hong;ZHANG Zong-lin;MENG Xing-min(School of Earth Sciences,Lanzhou University,Lanzhou,Gansu 730000,China;Technology&Innovation Center for Environmental Geology and Geohazards Prevention of Gansu Province,Lanzhou University,Lanzhou,Gansu 730000,China;College of Earth and Environmental Sciences,Lanzhou University,Lanzhou,Gansu 730000,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2022年第8期2305-2316,共12页
Rock and Soil Mechanics
基金
国家重点研发计划(No.2018YFC1504704)
国家自然科学基金青年基金项目(No.41602348)
甘肃省技术创新中心建设资助项目(No.18JR2JA006)
中央高校基本科研业务费专项资金(No.lzujbky-2021-sp01)。
关键词
无限边坡模型
降雨入渗
双重渗透模型
边坡可靠度
蒙特卡洛模拟
infinite slope model
rainfall infiltration
double permeability model
slope reliability
Monte Carlo simulation
作者简介
第一作者:姚云琦,男,1997年生,硕士研究生,主要从事边坡稳定性评价、黄土滑坡的学习与研究,E-mail:yaoyq19@lzu.edu.cn;通讯作者:曾润强,男,1987年生,博士,讲师,主要从事环境遥感与地质灾害、黄土滑坡的研究工作,E-mail:zengrq@lzu.edu.cn。
