Solving Method for Soil Spring Stiffness of Shallow Shield Tunneling
Dong Zhengfang,Wang Junjie,Zhao Dongxiao and Wang Wenbiao
DOI:10.11835/j.issn.1674-4764.2013.06.005
Received ,Revised , Accepted , Available online July 01, 2015
Volume ,2013,Pages 28-32
- Abstract
Based on complex variable theory in plane elasticity, the equivalent spring stiffness is derived from the analytical solution by means of simplifying shallow shield tunneling to semi-infinite plane with hole, which is applied to response displacement method. The performances of the analytical solution are evaluated and compared with that of the deep shield tunneling through a series of selected various tunnel depths and soil Poisson's ratios. The relation of compression and shear spring stiffness is discussed. Meanwhile, two factors affected soil spring stiffness, tunnel depth and soil Poisson's ratio, are also analyzed. It is shown that soil spring stiffness of shallow shield tunneling is different from that of deep shield tunneling, and the ratio of compression and shear spring stiffness varies along shallow shield tunneling. It is also found that the value and distribution law of soil spring stiffness of shallow shield tunneling greatly depend on tunnel depth and soil Poisson's ratio.