| 摘要 |
PURPOSE:To reduce the cost of construction work as well as to raise the safety of an offshore platform even when ice pressures are applied thereto by a method in which struts are erected on the lower base and loosely inserted into the central hole of an offshore platform, and an annular ice-breaking float bag with a conical slope face is provided. CONSTITUTION:A lower base 3 is provided on the seabed A, and a movable ice-breaking cone 5 is loosely inserted into the central hole and floated on water surface WL. A downward conical slope face 5a is provided to the base 5, and a seawater ballast tank 5b is also provided inside to make it vertically movable. When a bending action is applied to ice C on the slop face 5a, the ice C is broken and directed into water below the surface WL, thereby making the lateral sliding force smaller. The size of the lower base can thus be made smaller, and the position of the downward slope face of the cone can be optimumly adjusted with change of water depths. |
