A model test on a rigid pipe installation using J-lay method

Abstract

In this study, a series of model tests were carried out to evaluate an installation operation of a rigid pipe using J-lay method. It is assumed that an installation vessel equipped with a J-lay tower performs typical normal laying operation where a rigid pipe is lowered into the deep water. The model tests were carried out at Ocean Engineering Basin of KRISO. Regular wave tests were conducted under three vessel positions and two laying azimuth angle conditions. In this study, the main focus is on the tension responses of a rigid pipe and the reaction forces on roller boxes. The results of model tests are directly compared with the numerical simulation results. It can be found that the tension response of roller boxes is closely related to initial contact and gap distance between a rigid pipe and roller boxes. Also, it is confirmed that the top tension response of a rigid pipe is strongly affected by the vessel motion and the suspended pipe length. Discussion is made on the effect of the vessel position, the azimuth angle of a rigid pipe, and the gap distance of roller boxes. Copyright ？ 2018 by the International Society of Offshore and Polar Engineers (ISOPE)