摘要
土体的各向异性与沉积环境和应力历史密切相关。以能够考虑土体特性的各向异性不排水抗剪强度公式为基础,利用圆弧滑动方法,并考虑破坏面上强度的折减(τf=Su cosφ’),推导各向异性软土基坑抗隆起稳定极限平衡解。对软土基坑抗隆起稳定进行研究,系统分析了开挖深度H、围护结构插入深度D、最下道支撑与坑底相对距离He/H等几何因素及土体有效内摩擦角φ’、各向异性强度比k及强度沿深度非均质变化的斜率λ等强度参数的影响。最后结合工程实例,验证了公式的适用性,为软土基坑工程抗隆起分析提供了新的思路。
The anisotropic properties of soft clays are closely related to the sedimentary environment and stress history. Based on a theoretical formula of anisotropic undrained shear strength which take soft clay characteristics into account, this paper analyzes the soft clay stability against basal heave with slip circle method with consideration of strength reduction on the failure surface. The considered strength reduction formula can be expressed as τf=Su cosφ’, which means shear strength on the failure surface equals to the undrained shear strength times the cosine value of effective internal friction angle. Stability against basal heave of excavation is studied. Based on a number of examples, the influences of geometrical factors such as the excavation depth H, embedded depth D, and relative distance of the lowest support to the pit bottom He/H are analyzed. Strength factors such as the effective internal friction angle φ’, anisotropic strength ratio k and slope of heterogeneous shear strength versus depth λ are also investigated. Finally, the applicability of the formula is verified by the engineering example. This paper provides a new idea for the stability analysis against excavation basal heave.
作者
周建
蔡露
罗凌晖
应宏伟
ZHOU Jian;CAI Lu;LUO Ling-hui;YING Hong-wei(Research Center of Coastal and Urban Geotechnical Engineering,Zhejiang University,Hangzhou,Zhejiang 310058,China;Engineering Research Center of Urban Underground Development of Zhejiang Province,Hangzhou,Zhejiang 310058,China;Suzhou Changhong Architectural Design and Research Institute Co.,Ltd.,Gusu Branch,Suzhou,Jiangsu 215000,China)
出处
《岩土力学》
EI
CAS
CSCD
北大核心
2019年第12期4848-4856,4872,共10页
Rock and Soil Mechanics
基金
2016国家重点研发计划课题（No.2016YFC0800203）
国家自然科学基金重点项目（No.51338009）~~
关键词
软土
不排水抗剪强度
各向异性强度比
圆弧滑动方法
大主应力轴方向角
sofy clay
undrained shear strength
the anisotropy strength ratio
the arc sliding method
principal stress axis angle
