Preliminary Report of the Seaworthiness Characteristics of the Mohole Platform, Part I

摘要

Tests on a seaworthiness model of the MOHOLE Drilling Platform were conducted in regular and irregular waves at zero speed. Tests were conducted at drafts of 70, 50, and 26 feet corresponding to full scale displacements of 22,885, 19,690, and 14,350 long tons respectively. In order to obtain dynamic similitude for the 26 and 70-ft drafts, the ballast weights were properly positioned so that the vertical center of gravity and the natural periods were simulated as closely as possible. For the 50-ft draft these values were estimated. The measured natural heave, pitch, and roll periods of the model at the three drafts are shown. Wave lengths varied from about .7 to 6.7 times the model length in the regular wave tests. Tests were also made in programmed waves simulating Sea States 5 through 7. Measurements of pitch angle, roll angle, heave acceleration, wave height, surge acceleration, sway acceleration, and yaw angle were made. (Author)