摘要
【目的】探究山区渗流环境下基坑开挖对邻近高边坡变形的影响规律,揭示高边坡在渗流-应力耦合作用下的协同响应机制。【方法】以湖南某基础设施工程为研究对象,基于边坡-基坑耦合地质特征,采用圆弧条分法开展稳定性分析,结合现场监测数据与有限元数值模拟,对不同开挖深度下土体的水平位移、竖向变形及应力演化特征进行系统分析。数值模拟采用Mohr-Coulomb本构模型,并引入各向异性稳定渗流场实现渗流-应力的耦合分析。【结果】圆弧条分法所得最小安全系数与实测结果高度一致,验证了该方法的工程适用性;基坑水平位移随开挖深度的增大而显著增大,最大位移出现在边坡深度5 m处,最小位移位于基坑顶部;基坑底部发生明显塑性隆起,且隆起量与开挖深度呈正相关关系;周边土体竖向变形呈“勾”形分布,地表沉降最大值位于距基坑边缘15~20 m范围内,随后逐渐减小;高边坡竖向与水平变形值均随坡高的增加而增大,顶部土体所受扰动最为显著。【结论】高边坡协同变形的主要机制是渗流条件下基坑开挖引发的非均匀应力释放。所提出的理论计算与模拟分析方法可准确刻画该类工程的变形特征,可为复杂地质条件下邻近高边坡基坑工程的设计优化与变形控制提供理论依据与技术支撑。
[Purposes]This paper aims to investigate the influence law of foundation pit excavation on deformation of nearby high slopes under seepage conditions in mountainous areas and to reveal the synergistic response mechanism of high slopes under seepage-stress coupling.[Methods]A infrastructure project in Hunan Province was selected as the research object.Considering slope foundation pit coupling geological characteristics,the study applied the Swedish circle method to perform slope stability analysis,and a combination of field monitoring and finite element numerical simulation was used to analyze the horizontal displacement,vertical deformation,and stress evolution of soil at different excavation depths.A Mohr-Coulomb constitutive model and an anisotropic steady state seepage field were introduced to conduct seepage-stress coupling analysis.[Findings]The findings show that the minimum safety factor calculated by the Swedish circle method agrees well with monitoring data,validating the engineering applicability of the method.Horizontal displacement increases significantly with excavation depth,with the maximum occurring at 5 m below the slope and the minimum at the pit top.The pit bottom exhibits plastic uplift positively correlated with excavation depth.Vertical deformation of the surrounding soil displays a hook-shaped distribution,with the maximum surface settlement located 15-20 m from the pit edge.Vertical and horizontal deformation of the high slope also increases with elevation,with the crest showing the greatest response.[Conclusions]Non-uniform stress release induced by foundation pit excavation under seepage conditions is the main cause of synergistic deformation of high slopes.The combined theoretical and numerical approach proposed in this study can accurately describe the deformation characteristics of such projects and offer theoretical basis and technical support for deformation control and design optimization of similar foundation pit projects near high slopes in complex geological settings.
作者
王元明
张军
王佳仪
匡渝阳
WANG Yuanming;ZHANG Jun;WANG Jiayi;KUANG Yuyang(Central South Construction Group Co.,Ltd.,Changsha 410007,China;Hunan City University,Yiyang 413000,China;Zhejiang Daying Construction Co.,Ltd.,Hangzhou 311203,China;Zhejiang Jiaogong New Materials Co.,Ltd.,Hangzhou 311400,China)
出处
《交通科学与工程》
2025年第4期151-161,共11页
Journal of Transport Science and Engineering
基金
中南建设集团有限公司科研计划项目(JGYF-2024-012)
国家自然科学基金项目(51478049)。
关键词
岩土工程
高边坡基坑
渗流条件
数值模拟
变形监测
geotechnical engineering
high-slope foundation pit
seepage condition
numerical simulation
deformation monitoring
