| 摘要 |
<p>The present invention relates to a semi-rig having a plurality of columns (20) between a topside and a pontoon (10). A column (20) has an outer wall (20) having a plurality of through-holes (25) and a movable wall (30) to be moved to the outer side of the outer wall (22) to seal or expose the outer wall (22). Therefore, the semi-rig has motion performance to be optimized for environmental conditions of the sea area, which periodically change in accordance with seasons or at a specific time and combines restoration performance with motion performance.</p> |
