Study on The Design Method for The Entrance Wall of Circular Shaft That Takes into Account The Construction Sequences of The Diaphragm Wall and The Shield Tunnel

Abstract

This paper describes a method of reflecting the three-dimensional effects in a two-dimensional structural analysis for the design of a circular deep shaft of a shield tunnel entrance. The method is based on the result of three-dimensional FEM for different structural conditions whether there is any ring beam or inside wall for a body of the shaft. We conclude that in the design of the entrance with the shaft using two-dimensional structural analysis, the analysis requires an effect of a restraint of a convergence movement of the diaphragm wall. The effect is conducted by spring elements and the using of it is expected to leads to reasonable specifications for diaphragm wall and inside wall for a body of the shaft.