Dynamic response investigation of a small size floating dock unit in irregular oblique waves

Abstract

The floating dock units, according to the operation schedules, from time to time have to be relocated to different shipyards, involving river or costal routes. In this study, the dynamic behaviour of a small size floating dock during relocation is analyzed, with two constructive types of the floating structure above the dock pontoon deck and a maximum length of 60 m. By the floating dock and tug ship system resistance prediction, results a maximum towing speed around 18 km/h (9.72 kn). So, the numerical analysis is carried on for a set of five speed values, between 0 and 18 km/h. The dynamic response in irregular waves of the floating dock, full heading angle set, is computed by own program code. The irregular waves intensity is prescribed in terms of statistical wave significant height, with the maximum values corresponding to the Lower Danube River way and the Black Sea Coastal on Romanian area. The statistical dynamic responses, in terms of motion and acceleration significant amplitudes, are checked out against the short-term seakeeping criteria, in order not flood the dock pontoon deck. The study results are pointing out the limit navigation conditions for safety during the small size floating dock relocation operation.