| 摘要 |
PURPOSE:To enhance safeness to uplift of tunnel consisting of concrete segments by a method in which iron ores are used for part or all of aggregate in concrete segment. CONSTITUTION:A horizontal pit of a round cross section is excavated, and concrete segments 1 are assembled into a cylindrical form to form a tunnel 2 following the excavation. In this case, iron ores are used for part or all of aggregate in the concrete segment 1 to increase the unit volume weight of the concrete segment 1. |
