Abstract
In recent years, many shield tunnels with shallow overburden have been constructed for the purpose of cost reduction in construction of vertical shafts. Such shield tunnels are constructed in soft ground, they are strongly affected by earthquake.
In this article, a composite segment employed at a construction site of Keiyo-Junction is picked out as an example for an analysis, and the result based on the demostration experiment of segment joints, are described. By performing demonstration experiments and an analysis, the load-bearing mechanism and fructure behavior of segment joints which are subject to high tensile force are shown, and the method and result for reinforcement of such segment joints are considered. Also, impact of rotational spring of segment joints is examined.
