EXPERIMENTAL STUDY OF THE DYNAMICS OF A LARGE-TONNAGE BULK CARRIER MOORED AT A BERTH UNDER THE ACTION OF REGULAR WAVES

Abstract

Introduction. The development of modern port infrastructure increasingly involves the construction of berthing facilities in insufficiently protected water areas. Under such conditions, wave-induced motions of moored vessels may significantly affect the safety and efficiency of cargo-handling operations and increase the risk of damage to both ships and quay structures. Regular waves are of particular concern, as they can cause pronounced oscillatory responses and resonance effects, especially in shallow water conditions. Therefore, experimental investigation of moored ship dynamics remains an important engineering task. Purpose. The purpose of this study is the experimental determination of linear and angular motion characteristics of a large-tonnage bulk carrier moored at a quay under regular wave action in shallow water. An additional objective is the validation of an analytical ship motion model and the assessment of simplified engineering criteria for evaluating the admissibility of vessel motions during port operations. Results. The study was carried out in an experimental basin using a physical ship model designed according to the Froude similarity criterion. Two load conditions were considered – at full load and with 50 % load and full reserves for both cases. Ship motions were measured using accelerometers and inclinometers installed near the model’s center of gravity. Experimental data were processed using fast Fourier transform techniques. The results show that partial loading leads to increased amplitudes of vertical and longitudinal motions and longer oscillation periods. In contrast, full loading reduces motion amplitudes due to higher inertial properties. Transverse and yaw motions remained negligible. A satisfactory agreement between experimental results and analytical predictions was obtained. Conclusions. The study confirms the significant influence of loading condition on the dynamic behavior of a moored vessel. Physical modeling has proven to be an effective tool for assessing the safety of ship berthing under regular wave conditions. The proposed approach can be applied in port design and operation practice to justify allowable operating conditions and mooring arrangements without performing complex numerical simulations.