| 摘要 |
PURPOSE:To cut down the cost of construction for an offshore working platform by a method in which vertically movable legs are provided to a pontoon in which upper deck is supported thrugh struts on a water-chargeable body, and they are fixed during the working period in such a way that the varying position B of water level is within the range of the strut portion. CONSTITUTION:An offshore working platform is towed to a given position and positioned by an anchor 9, and legs 2 are lowered by an elevator 3 and driven into the ground of seabed. A pontoon 1 and the legs 2 are freed, water is charged into the body 4 to lower the pontoon 1, and the body 4 is sunk into water. Where the varying position B of water level is within the range of struts 5 portion during the ebb and flow period, the pontoon 1 and the legs 2 are fixed. Since the pontoon 1 is given a buoyancy, burden of the legs is lessened, the elevator used can be miniaturized, and the cost of construction can be reduced. |
