| 摘要 |
PURPOSE:To prevent the entrance of muddy soil and sand into an excavation hole and to improve a working efficiency, by a method wherein a mortar releasing port is formed in an excavation forward end cone, and in the case of a soft ground, mortar can be implanted in a manner to embed the forward end cone in a ground. CONSTITUTION:An excavation forward end cone 20 is constituted such that a plural number of right-angled triangular plates 24 is located in a radial manner. A flange 26 is mounted on the short side of the triangular plate 24, a screwform or rodform excavating cutter 25' is securely attached to the oblique side of the triangular plate 24, and a mortar releasing port 53 is provided. A ground is excavated through turning of a cylinder 33 having a screw vane 30 and a shaft 19 for spinning the forward end cone 20. Mortar is then implanted into a hollow pipe 10, a piston 7 is depressed, and the valve at the forward end cone is opened to place mortar, working as a consolidating material, into a ground through the mortar releasing port 53. Then, the forward end cone 20 is raised, and after a pile is driven, the screw vane 30 is removed. |
