シールドトンネルの耐震解析に用いる長手方向覆工剛性の評価法

抄録

This paper presents a practical method to evaluate the longitudinal stiffness of shield tunnel linings which is of great importance in the seismic response analyses of shield tunnels. Linings of shield tunnels are constructed assembling a number of segments and joints, and have structural discontinuity in the longitudinal direction. In this paper, relationships between stress and deformation of segments-joints system, both for axial force and for bending moment, are formulated into the form of “equivalent stiffness”, i. e., the stiffness of uniform beam having the same stress-deformation relation as that of segments-joints system.
Modeling the lining into a uniform beam with the equivalent stiffness, it makes possible to analyze behavior of shield tunnels by means of seismic deformation method as well as other pipe-like underground structures. Parameters which have influence on the equivalent stiffness are also discussed.