태풍매미에 의한 부산항 컨테이너크레인의 붕괴

Abstract

Large container cranes are normally designed to resist severe wind. Safety devices such as stowage pins and tie-downs prevent them from being slided or overturned. However, even when the wind speed a little bit exceeds design level, they sometimes undergo total collapse. This may be due to the fact that the total force exerted on the structure increases in proportional to the square of wind speed. But, another important fact is uncovered in this study. Tensions occurring at tie-downs increase much faster than that of main bodies. Therefore, very small amount of excessive wind speed may cause fatal increases of tension at tie-downs. The increasing rate of wind speed and the member force of safety devices were compared in numerical example and it was also proved theoretically. One of the most probable causes of collapsed container cranes at Shingamman port, Busan, was revealed by this phenomenon. In conclusion, it is recommended that safety factor for mooring devices should be larger than that for structural members