PROPOSAL OF STRUCTURAL ANALYSIS METHOD FOR CIRCULAR DEEP SHAFT WITH OPENING FOR SHIELD TUNNEL

Abstract

 Since the stress around the opening of a circular shaft is complicated, it is difficult to properly model it in 2D analysis, and a vertical 2D beam model that is designed for safety is used based on past experience and experience. Often. However, it is not economical compared to the 3D model, and its effect is considered to be large especially when the opening is large. On the other hand, FEM analysis using a 3D model is very complicated, and the design method is not systematized, and the evaluation is based on the designer’s judgment.

 Therefore, in this study, by using 3D FEM analysis, we investigated the effects of an opening and a rail beam on the circular deep shaft behavior around the opening. We propose a rational 2D modeling method for the sidewall of the opening considering the 3D effect.