考虑土体空间变异性的管廊基坑开挖过程中变形及能量演化特征分析  

Analysis on Deformation and Energy Evolution Characteristics during Pipeline Gallery Foundation Pit Excavation Considering Soil Spatial Variability

作　　者：陈扬 袁宗义[2] 梁禹 CHEN Yang;YUAN Zong-yi;LIANG Yu(College of Management and Economics, Tianjin University, Tianjin 300072, China;CCCC-FHDI Engineering Co., Ltd., Guangzhou 510290, China;School of Aeronautics and Astronautics Engineering, Sun Yat-sen University, Shenzhen 518107, China)

机构地区：[1]天津大学管理与经济学部,天津300072 [2]中交第四航务工程勘察设计院有限公司,广州510290 [3]中山大学航空航天学院,深圳518107

出　　处：《科学技术与工程》2022年第17期7127-7134,共8页Science Technology and Engineering

基　　金：广东省基础与应用基础研究基金(2020A151501271);深圳市自然科学基金可持续发展专项(KCXFZ20201221173207020)。

摘　　要：基坑开挖工程的稳定性受所在区域土体参数的空间变异性影响较大,其施工过程伴随着基坑内部能量的相互转化,为研究复杂多层土基坑开挖过程中土体参数的空间变异性影响及能量演化特征,依托佛山市某综合管廊基坑项目,基于中心点法建立了多层土的弹性模量随机场模型,结合FLAC软件构建了复杂多层土的随机场-有限差分耦合计算基坑开挖的数值模型。研究结果表明:基于随机场参数的统计分析及位移实测对比分析验证了所建立模型的准确性;基于均质模型与随机场模型的测点变形趋势一致,但不同测点处位移的变异性存在显著差别,基坑总体变形可控;基坑开挖过程中,弹性应变能的一部分转化为塑性应变能,开挖完成后基坑处于稳定状态。The stability of a foundation pit excavation project is greatly affected by the spatial variability of the soil parameters in the area.The construction process was accompanied by the mutual transformation of the internal energy of the foundation pit.In order to study the spatial variability and energy evolution characteristics of soil parameters during excavation of complex multi-layer foundation pit,a foundation pit project of a comprehensive pipe gallery in Foshan was taken as the research object.Elastic modulus random field model of multilayer soil was established based on the midpoint method.Then,the numerical model of foundation pit excavation with random field and finite difference coupling was built using FLAC.The research results show that the accuracy of the numerical model is verified by the statistical analysis of random field and the comparative analysis of displacement actual measurement.The deformation trend of the measuring points is the same between the homogeneous model and the random field model,and the deformation of the foundation pit is controllable.Part of elastic strain energy is converted into plastic strain energy during the excavation of the foundation pit,and the foundation pit is in a stable state after the excavation is completed.

关 键 词：基坑开挖 随机场 能量演化 有限差分模拟 

分 类 号：TU753[建筑科学—建筑技术科学]