基于强度折减法的淤泥质基坑坑底抗隆起稳定性研究  

Study on anti-uplift stability of silt foundation pit bottom based on strength reduction method

作　　者：杨沛基 张军[1] 严鹏 YANG Peiji;ZHANG Jun;YAN Peng(School of Safety Engineering,North China Institute of Science and Technology,Yanjiao,065201,China;China Nuclear Industry No.24 Construction Co.,Ltd.,Beijing,101601,China)

机构地区：[1]华北科技学院安全工程学院,北京东燕郊065201 [2]中国核工业二四建设有限公司,北京101601

出　　处：《华北科技学院学报》2022年第3期68-74,共7页Journal of North China Institute of Science and Technology

基　　金：中国核工业二四建筑有限公司科研项目(KY2020-04)。

摘　　要：坑底抗隆起稳定性是淤泥质基坑工程支护设计的关键要素。以霞浦核专家村基坑工程为背景,通过有限元强度折减法、抗隆起验算及与现场监测结果对比的方法,主要从淤泥质坑底隆起破坏机理、基坑开挖深度、土体参数、坑底淤泥层厚度及时间效应五个方面研究淤泥质基坑坑底抗隆起稳定性。结果表明:沿海地区淤泥质基坑坑底抗隆起稳定性不仅受空间效应影响,也受时间效应的影响;基坑开挖深度、土体重度γ、淤泥质土层厚度及基坑暴露时间与抗隆起稳定安全系数的关系曲线呈下降趋势;粘聚力c和内摩擦角?与抗隆起稳定安全系数的关系曲线呈上升趋势。研究成果可为此类的淤泥质基坑支护设计提供参考。The anti-uplift stability of the pit bottom is the key factor in the support design of the muddy foundation pit.Taking the foundation pit project of Xiapu Nuclear Expert Village as an example,based on the finite element strength reduction method,anti-heave checking calculation and comparison with the field monitoring results,the anti-heave stability of the bottom of the muddy foundation pit was studied from five aspects such as the failure mechanism of the bottom heave of the muddy foundation pit,the excavation depth of the foundation pit,the soil parameters,the thickness of the bottom silt layer and the time effect.Foundation pit excavation depth and soil mass weightγ、The relation curve between the thickness of mucky soil layer and the exposure time of foundation pit and the anti heave stability safety factor shows a downward trend.At the same time,cohesion c and internal friction angleφThe relation curve with the anti heave stability safety factor shows an upward trend.The research results can provide reference for the support design of such muddy foundation pits.

关 键 词：淤泥质基坑 抗隆起稳定性 强度折减法 安全系数 

分 类 号：TU473[建筑科学—结构工程]