Experimental investigation on dynamic response of a floating buoy with intact and broken mooring system

The floating buoy exhibits large dynamic responses subjected to extreme ocean environmental conditions, easily leading to mooring failure events. The impact of mooring failure on the dynamic response of buoy needs to be studied. However, the hydrodynamic performance of buoy with the broken mooring system have not been comprehensively illustrated. A series of experiments are performed on the dynamic responses of a floating buoy in a wave basin. The motion responses and mooring tensions with the intact and broken mooring system are measured for the regular and irregular wave tests. The transient failure of a single mooring line and progressive failure of mooring system are investigated. The results indicate that the peak tension of the upwind mooring line tends to increase linearly with the increase of significant wave height. With the development of failure process, the motion responses tend to increase and the buoy gradually moves to a new equilibrium position. The progressive failure of mooring system leads to significantly increase in the sway and yaw motion directions, resulting in the extensive drift motion of the buoy. The results could be helpful to illustrate the mooring system failure mechanism and prevent further damage of buoy in shallow waters.