Laws of Surface Subsidence Caused by the Excavation of a Bored Subway Tunnel in a Water-Rich Mixed Ground in Shenzhen
(1 School of Civil Engineering, Beijing Jiaotong University, Beijing 100044;
2 China Railway Southern Investment & Development Group Co. Ltd., Shenzhen 518055)
Abstract：
In urban metro design, it is necessary to understand the laws of surface subsidence caused by subway tunnel construction. Using the Shenzhen Metro Line 5 as an example, over 22,000 surface subsidence monitoring data were properly selected from 19 bored running tunnels for a statistical analysis, and the laws of the longitudinal and transverse distribution as well as the variations of the surface subsidences along the tunnel in each bored running tunnel were obtained. The results show that the distribution law of the maximum accumulative surface subsidence in each running tunnel is uneven (with an average of 82.3mm, a maximum of 688.7mm and a minimum of only 7.8mm) and the range of transverse surface subsidence in the tunnel is different from one another (with a maximum of 140.47m, minimum of 28.63m and average of 46.78m). Because of the large differences between the measured data and the maximum surface settlement control standards allowed by existing specifications, adoption of the new three-level control baseline that is suitable for controlling the surface subsidence caused by the bored excavation of subway tunnels in water-rich mixed ground is suggested for reasons of economy and rationality.
LI ,
TAO 1,
HAN Xue-Feng-2 etc
.Laws of Surface Subsidence Caused by the Excavation of a Bored Subway Tunnel in a Water-Rich Mixed Ground in Shenzhen[J] MODERN TUNNELLING TECHNOLOGY, 2014,V51(2): 76-82
2014, Vol. 51 