| 摘要 |
PROBLEM TO BE SOLVED: To provide an invert block capable of maintaining the state of being fixed to a steel shield segment, even when being subjected to repeated live loading and vibrations, and a method for fixing the invert block.SOLUTION: Three plate metal fittings for welding are arranged in an invert block 1 in such a manner as to assume a triangular shape in a plan view, and the invert block 1 is welded and fixed to a steel shield segment via the metal fittings for welding in the state of being supported at three points.SELECTED DRAWING: Figure 2 |
