基于分离相似概念的地铁异形基坑三维开挖模型试验  

THE MODEL TEST OF THE IRREGULAR FOUNDATION PIT OF THE SUBWAY BASED ON THE RESPECTIVE SIMULATION THEORY

作　　者：黄明[1] 江松[1] 邓涛[1] 张乃烊 叶其彬 沈启炜[4] HUANG Ming;JIANG Song;DENG Tao;ZHANG Naiyang;YE Qibin;SHEN Qiwei(School of Civil Engineering,Fuzhou University,Fuzhou 350116;Fuzhou Planning Design Research Institute,Fuzhou 350108;Xiamen Municipal Engineering Design Institute Co.,Ltd.,Xiamen 361004;China Railway 18 Bureau Group Co.,Ltd.,Tianjin 300222)

机构地区：[1]福州大学土木工程学院,福州350116 [2]福州市规划设计研究院,福州350108 [3]厦门市市政工程设计院有限公司,厦门361004 [4]中铁十八局集团有限公司,天津300222

出　　处：《工程地质学报》2018年第2期384-390,共7页Journal of Engineering Geology

基　　金：国家自然科学基金(41672290);福建省自然科学基金(2016J01189)资助

摘　　要：以厦门吕厝站地铁基坑开挖工程为工程原型,采用分离相似设计方法确定了模型试验所需要关键参数的相似比,制作了异形基坑试验模型,并设计了合理的监测系统。通过模拟基坑实际的开挖过程,根据取得的监测数据,分析了地表沉降、地连墙变形和受力等变化规律。结果表明:与基坑边缘距离越大,地表沉降影响越小,且墙体边长及开挖深度越大沉降越显著;地表沉降曲线形式与沉降数值大小有关,基坑开挖表现出明显的空间效应和角隅效应,地表沉降主要发生在坑内土体开挖阶段;随开挖的进行,土层卸荷对地表沉降影响逐渐减小,地连墙弯矩大小与开挖深度呈正相关,最大弯矩值出现在基坑最深开挖面附近。According to the foundation pit excavation of the Lücuo station in Xiamen Subway Line 1,the similar ratio of the key parameters of the model is obtained with the respective similitude theory.Besides,the whole model is made and the monitoring system is designed.By simulating the actual excavation process and analyzing the monitoring data,the ground settlement,the deformation and stress distribution of the diaphragm are given.The results show that,the ground settlement is negatively correlated with the distance away from the diaphragm and positively correlated with the length of the diaphragm and the depth of excavation.The shapes of the curve are related to the total settlement caused by the excavation unloading,and the spatial and corner effect are obvious.The ground settlement mainly occurs in the stage of excavation.The influence of excavation on the ground settlement is gradually reduced with the excavation progress developing.The bending moment of the diaphragm is positively correlated with depth of excavation.The maximum bending moment of the diaphragm is at the excavation face of the foundation pit.

关 键 词：分离相似理论 模型试验 异形基坑 地铁车站 

分 类 号：TV551.41[水利工程—水利水电工程]