Effective Arrangement of Rubber Fenders of Wind-Measuring Met Mast Due to Boat

摘要

The main object of this research is to minimize the shock effects which frequently result in fatal damage to the wind-measuring met mast after impact with a service boat. The collision between wind-measuring met mast and service boat is generally a complex problem, and it is often impractical to perform rigorous finite element analyses to include all effects and sequences during the collision. This paper focuses on the structural behaviors of the wind-measuring met mast. A significant part of the collision energy is dissipated in terms of strain energy, and the contribution from the elastic strain can normally be neglected. On applying the impact force of a service boat to the wind-measuring met mast, the maximum acceleration, internal energy and plastic strain are calculated for each load case using the finite element method. LS-dyna, a commercial explicit finite element code from ANSYS software, is used to produce a finite element model and analyze the nonlinear responses of the met mast due to the service boat collision. A parametric study is carried out by changing design variables of the service boat's velocity and the thickness of the wind-measuring met mast. Three types of materials for rubber fenders are taken into account where Mooney-Rivlin coefficients are determined based on the experimental data. It is assumed that the effect of the wave-induced vertical motion of a service boat is negligible. It is concluded that this paper provides a designing process used for rubber fenders considering a service boat impact.