Experimental investigation on motions behavior and loads characteristic of floatover installation with T-shaped barge

Abstract

Transferring topsides loads fast and safely by the jacking and ballast systems, as well as increasing the stability and reducing the platform slot requirement by a T-shaped barge, enable the floatover installation suitable to the harsh environment conditions. The paper presents the experimental study on the floatover installation with the T-shaped barge, in which the topsides loads were transferred by the ballast system and the jacking system. Several phases of the floatover installation including 0%, 30%, 70% and 100% load transfer phases were experimentally modeled. Both motions of the barge and the topsides and loads on the Deck Support Unite (DSU) and the Leg Mating Unite (LMU) were investigated at different intermediate load transfer phases. Results demonstrate that the trim angle of the barge varies significantly as the increase of the load transferred. The standard deviation of DSU loads and the significant value of LMU loads at the 70% load transfer phase are much larger. The following waves induce larger surge motions and are more dangerous than the heading waves. Comparisons indicate that the floatover installation is sensitive to the wave periods and the swell waves would threat the feasibility of the floatover installation.