Dynamic factor analysis considering elastic boom effects in heavy lifting operations

The dynamic factor is the ratio of the maximum dynamic load to the static load acting on the wire ropes between the boom of a floating crane and a cargo. In this paper, the dynamic factor is analyzed based on dynamic simulations of a floating crane and a cargo, considering an elastic boom. For the simulation, we designed a multibody system that consists of a floating crane barge, an elastic boom, and a cargo connected to the boom through wire ropes. The dynamic equations of motion of the system are based on flexible multibody system dynamics. Six-degree-of-freedom motions are considered for the floating crane and for the cargo, and three-dimensional deformations for the elastic boom. The hydrostatic force, the hydrodynamic force, the gravitational force, and the wire rope forces are considered as external forces. The dynamic factor is obtained by numerically solving the equation. The effects of the elastic boom on heavy cargo lifting are discussed by comparing the simulation results of an elastic boom and a rigid boom. (C) 2011 Elsevier Ltd. All rights reserved.