Study on the Reasonable Overlying Strata Thickness for Metro Tunnel through the Raft Foundation Buildings in Upper-soft and Lower-hard Strata

2018 International Conference on Civil, Architecture and Disaster Prevention

土木建筑工程

Zhang, Ziguang^1

School of Civil Engineering, Anhui Jianzhu University, Hefei

230601, China^1

关键词: Design and construction;    Engineering practices;    Field monitoring data;    Inversion analysis;    Numerical calculation;    Overlying strata;    Raft foundations;    Reference values;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/218/1/012112/pdf
DOI  :  10.1088/1755-1315/218/1/012112

学科分类：土木及结构工程学

来源: IOP

【 摘 要 】

This paper was based on the engineering practice of Qingdao metro tunnel through a raft foundation. The methods of numerical calculation and inversion analysis of field monitoring data were used to analyze the reasonable overlying strata thickness for metro tunnel through the raft foundation buildings in upper-soft and lower-hard strata. The concept of reasonable overlying strata thickness was proposed based on full utilizing the self-stability of surrounding rock when the metro tunnels through the raft foundation. It was pointed out that the self-stability of surrounding rock increased rapidly with the increase of overlying strata thickness firstly, and tended to stabilize when the overlying strata thickness reached a certain value; and then the influence of the overlying strata thickness on self-stability was not obvious thereafter. The reasonable overlying strata thickness for the metro tunnels through the raft foundation was about 5.0 ∼ 6.0 m in the upper-soft and lower-hard strata in Qingdao. The research conclusion had certain reference value for the design and construction of the metro tunnels through the raft foundation safely, economically and quickly.