Numerical analysis and experimental study on the scaled model of a container ship lashing bridge

Abstract

Most existing studies and standards for containers and lashing equipment correspond to static conditions, which stresses current imperfections in the design specifications of the lashing bridge structure and gaps in experimental research. In this paper, an approach is proposed to study the mechanical behavior of the ultra-large containership lashing bridge structure. Based on Buckingham's Theorem and the Froude scaling laws, a scaled model test system with a container stack and twist lock is developed for a systematic experimental study of the lashing bridge. Additionally, the numerical analysis of the static, modal and dynamic response were carried out under the typical motion of the lashing bridge. Also, the coupling effect of the lashing bridge and hull structure is considered to design the system. The physical (size, mass, and moment of inertia) and structural characteristics (longitudinal, lateral, and torsional stiffness) of the proportional model are determined by two dimensionless numbers: Froude's number and Cauchy's number. The results suggest that the mechanical behavior of the ultra-large containership lashing bridge structure can be easily obtained from the reduced model. This can help to achieve the structural design and optimization, and the substructure coupling analysis of ultra-large lashing bridges.