摘要
深基坑工程围护结构主动土压力是设计、施工中需考虑的一个重要因素,实践表明土压力大小与围护结构变形密切相关,经典的朗肯、库仑土压力理论并未考虑围护结构变形对土压力的影响。首先介绍了一种考虑位移的主动土压力计算理论;其次基于静止土压力、考虑位移的主动土压力、朗肯主动土压力的含义,以及考虑位移的主动土压力介于静止土压力与朗肯主动土压力之间的特点,提出了朗肯主动土压力接近度η的概念;然后利用统计分析的理念,采用Beta分布描述η的分布规律,基于福州地铁2号线上街站基坑工程中24个地下连续墙变形测点监测数据对其进行统计分析,获得了η的分布特点;结合η随土层埋深的变化特点及其概率分布F(η)提出了一种适用于软土深基坑的主动土压力计算模型;最后基于某软土深基坑工程实测主动土压力验证了所提方法合理性。
Active earth pressure of retaining structure of deep foundation pit engineering is an important factor to be considered in design and construction.Practice shows that the magnitude of earth pressure is closely related to the retaining structure deformation,but the classical Rankine and Coulomb earth pressure theory does not consider the influence of the retaining structure deformation on the earth pressure.Firstly,an active earth pressure calculation theory considering displacement was introduced.Secondly,Rankine active earth pressure proximityηwas defined based on the meaning and characteristic of static earth pressure,active earth pressure considering displacement and Rankine active earth pressure.By using the idea of statistical analysis the Beta distribution was used to describeη.Based on the monitoring data of 24 deformation measuring points of diaphragm wall in the foundation pit of Shangjie station of Fuzhou Metro Line 2,the distribution characteristics ofηwere obtained.An active earth pressure calculation model suitable for soft soil deep foundation pit was proposed based on the variation ofηwith soil depth and its probability distribution F(η).Finally,the rationality of the proposed method was verified by comparing it with the measured active earth pressure of a soft soil deep foundation pit project.
作者
李明
LI Ming(College of Civil Engineering,Fujian University of Technology,Fuzhou 350118;Key Laboratory of Underground Engineering,Fuzhou 350118)
出处
《现代隧道技术》
CSCD
北大核心
2022年第S01期495-501,共7页
Modern Tunnelling Technology
基金
福建省自然科学基金(2021J011061)
福建省教育厅中青年教师教育科研项目(JAT210295)
福建工程学院科研启动基金(GY-Z18139)
关键词
基坑工程
主动土压力
地下连续墙变形
概率统计
Foundation pit engineering
Active earth pressure
Deformation of diaphragm wall
Probability statistics
作者简介
李明(1988-),男,博士,讲师,主要从事地下工程领域的安全评价研究工作,E-mail:lm20080808@126.com.
