| 摘要 |
PURPOSE:To reduce the construction cost of a tunnel by setting the outside diameter of the cutter of a shield greater than that of a skin plate, and packing excavated earth and sand with a solidifier on the outside of the skin plate, thereby forming primary lining. CONSTITUTION:A primary lining layer A is formed on the outside of the cylindrical skin plate 10 of a shield by mixing earth and sand excavated by the projecting portion 16 of a cutter 11 with a solidifier and packing the mixture. While a tunnel is excavated, the primary lining layer A is formed progressively by use of the surplus soil of excavation and a secondary lining layer B is formed inside. The construction cost of the tunnel can thus be reduced by disposal of the surplus soil and reduction in lining. |
