Influence of soft clay structure on pit excavation and adjacent tunnels

被引：4
|
作者：
Wang C. [1 ,2 ,3 ]
Ling D.-S. [1 ,2 ,3 ]
Wang H.-Y. [2 ,3 ]
机构：
[1] Institute of Geotechnical Engineering, Zhejiang University, Hangzhou
[2] MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, Zhejiang University, Hangzhou
[3] School of Civil Engineering and Architecture, Zhejiang University Ningbo Institute of Technology, Ningbo
来源：
Zhejiang Daxue Xuebao (Gongxue Ban)/Journal of Zhejiang University (Engineering Science) | 2020年 / 54卷 / 02期
关键词：
Artificial structured soil; Disturbance degree; Laboratory test; Pit excavation; Tunnel;
D O I：
10.3785/j.issn.1008-973X.2020.02.007
中图分类号：
学科分类号：
摘要：
One-dimensional compression test and triaxial test were conducted based on the undisturbed silty clay of Ningbo and artificial structural soils, in order to analyze the influence of soil structure on deformation of retaining wall, ground settlement and displacement and bending moment of adjacent tunnels during pit excavation. The artificial structural soils were made by adding salt and cement of different mass fractions in the remolded soil. The relationship between mass fraction of cement and soil structure was verified and established through compressibility indexes, shear strength indexes and yield stress. The Plaxis2D was used to analyze the influence of soil structure on horizontal displacement of retaining walls, settlement of ground surface and adjacent tunnels. Results show that when the mass fraction is 2%, the compressibility indexes, shear strength indexes and structural yield stress are basically the same as that of the undisturbed soil. As the structure of the soil decreases, namely the degree of disturbance increases, the displacements of the retaining walls, ground surface and adjacent tunnels increase rapidly. The tunnel is most sensitive to the degree of disturbance, and its displacement growth trend is the most obvious. When the disturbance degree reaches 39%, the tunnel displacement exceeds the allowable value. When the tunnel is closer to the pit, the displacements of retaining wall and ground surface decrease due to the the constraint effect of the tunnel, while the tunnel displacement and bending moment increase accordingly. © 2020, Zhejiang University Press. All right reserved.
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页码：264 / 274
页数：10
相关论文
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