부산대학교 도서관

The floating cranes in the world market is approximately 14 trillion won by 2009, the domestic market accounted for 11.4%. Floating cranes are used for construction and installation work of the harbor, various heavy industries, and marine structures. Furthermore, floating cranes are used in bridges and civil engineering projects. By utilizing the cranes, large structures can be installed quickly and easily, and there are many economic advantages, such as saving installation time and safety. When working with a floating crane, it requires a high level of safety and precision, and when designing the floating crane, the economy efficiency should be considered. In Korea, although safety evaluation method is introduced with the finite element method, it is made mainly crane control design and parts analysis. Safety evaluation of applications including buckling, deformation, stress, and vibration of the main member for the entire structure is insufficient. In the case of floating cranes that they need to move around at seat to work, they can be constrained to navigate. The south coast and the west coast have many marine bridges. Therefore, floating cranes are constrained to pass along the marine bridge. In particular, Korea has the 75 marine bridges, and even though the height of the marine bridges is displayed, the vertical distance between the surface of the water and marine bridge is so low that floating cranes cannot pass under the marine bridges.In this study, the height of the marine bridge and the passage of the minimum luffing angle of the floating cranes were investigated. According to analysis of problems that are happened when the floating crane passages, and improvements of boom luffing angle of the floating crane, the floating cranes can passage easilyIn this study, The 250ton floating crane development model based on upper part of floating crane consisting of crane boom, back tower and support was modeled to fit the design criteria. A characteristic of floating crane is analyzed when passing though the lower marine bridge of the luffing condition. Structure strength and structure safety evaluation is conducted according to KR-Rule about service condition, stowage condition and luffing condition based on loading condition and load combinations.