Structural vibrations calculation and testing of the heavy lifting appliance

摘要

Mechanical model of a hoisting appliance for standard ship containers (container crane) is made on the basis of finite elements method (FEM) and its vibration analyssi is performed. The properties of the beams are modelled as line beam elements with the formulation for stretching, bending, torsion and transverse shear deformation effects. The actual hoisting appliance, for which the results are presented is the container crane with the load carrying capacity of 325/380 kN, product of Metalna Slovenia, stationed in Bangkok port, Thailand (Fig.1). Results of dynamic analysis of a box beam (reinforced with inner ribs) modelled with the mentioned line and 3D sheel elements are compared. On account of a rather large dead weight (4700 kN) of the crane, the effect of the second order theory (geometric nonlinearity) on the eigenvalues and eigenmodes is estiamted. To define the damping values and validate the modeling strategy an experiment on the similar structure was performed. The test and numerical results of the mentioned structure resonance frequencies and vibration mode shapes are compared.