考虑SWCC随机特征的超固结红黏土边坡稳定性分析  

Stability analysis of over-consolidated red clay slope considering SWCC random characteristics

作　　者：王长虹 闫宇 杜昊东 胡世韬 蔡德雍 WANG Changhong;YAN Yu;DU Haodong;HU Shitao;CAI Deyong(School of Mechanics and Engineering Science,Shanghai University,Shanghai 200444,China)

机构地区：[1]上海大学力学与科学工程学院,上海200444

出　　处：《自然灾害学报》2025年第2期99-109,共11页Journal of Natural Disasters

基　　金：上海市社会发展科技攻关项目(21DZ1204300);江西省交通运输厅科技项目(2021H0037)。

摘　　要：在分析超固结非饱和红黏土边坡的稳定性时,仅考虑边坡土的强度指标,易导致分析结果与边坡实际力学状态不相符合。因此,考虑非饱和红黏土的水力特性,以土水特征曲线(soil-water characteristic curve,SWCC)的随机统计特征为基础,修正超固结非饱和统一硬化(unified hardening,UH)模型,开展红黏土边坡的稳定性研究。以江西省九江市长虹大道的红黏土公路边坡为研究对象,首先,基于有限的室内试验数据,引入贝叶斯理论,校准Van Genuchten(VG)和Fredlund-Xing(FX)模型的随机统计特征;其次,提出类双曲线函数,表征红黏土的吸力强度规律,改进红黏土的超固结非饱和UH模型;然后,结合SWCC模型参数的随机统计特征,开展红黏土边坡的渗流场分析;最后,通过开发改进的UH模型程序,计算公路边坡的最大水平位移,与采用摩尔-库伦模型计算的位移,开展对比分析。研究结果验证了红黏土的超固结非饱和UH模型的有效性,表明雨季易发生滑坡灾害。Analysis of the stability of over-consolidated unsaturated red clay slopes solely based on strength indicators may lead to consequences that do not match the actual mechanical state of the slope.Hence,taking the hydraulic characteristics of unsaturated red clay into account,based on the random statistics of the soil-water characteristic curve(SWCC),the over-consolidated unsaturated unified hardening(UH)model is modified to reasonably study the stability of red clay slopes.The research focuses on a red clay highway slope along Changhong Avenue in Jiujiang City,Jiangxi Province.Firstly,Bayesian theory is used to calibrate the random statistics of the SWCC models,including Van Genuchten(VG)and Fredlund-Xing(FX)model.Secondly,a hyperbolic-like function is proposed to characterize the suction strength relationship of the red clay and improve the over-consolidated unsaturated UH model of red clay.Subsequently,combined with the random statistics of the SWCC model parameters,the seepage field of the red clay slope is analyzed.Finally,a comparative analysis is conducted between the horizontal displacement of the highway slope calculated by the improved UH model of red clay and the Mohr-Coulomb model.The results verify the effectiveness of the over-consolidated unsaturated UH model of red clay,and indicate that landslide disasters are prone to occur during the monsoon season.

关 键 词：土水特征曲线 贝叶斯理论 红黏土边坡 吸力强度 UH模型 

分 类 号：TU411[建筑科学—岩土工程] X43[建筑科学—土工工程]