On the Design of Lifting Lugs Based on the Ultimate Strength

최종강도에 기초한 리프팅 러그의 설계

Lee, Joo-Sung

  • Received : 2015.09.14
  • Accepted : 2015.11.16
  • Published : 2016.02.28


Lifting lugs are frequently used to transport and to turn over blocks of ship and offshore structures in a shipyard. As the shipbuilding technology has been developed, blocks has become bigger and bigger, and block management technology takes a more important role in shipbuilding to enhance the productivity. For the sake of economy as well as safety in design of lug structure, needed is a more rational design procedure based on the ultimate strength derived through the rigorous non-linear structural analysis considering both the material and geometric non-linearity. This study is aimed at deriving the optimum design of T type lug structure which is frequently used in a shipyard. The optimum thickness of lug's main body is to be determined based on the results of non-linear strength analysis. As far as the present results for T type lugs having various capacity are concerned, it can be said that the present optimum design result can guarantee both safety and economy. From the fact that any regular trend cannot be found in weight reduction to the capacity of lugs, it seems to be necessary to review the current design procedure of lug structure. The present design procedure can be extensively used in design of various types of lug structures used in shipyard.


non-linear structural analysis;optimum design;T type lug;ultimate strength;weight reduction


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