Response of a tension leg platform to stochastic wave forces

The equations of motion and the response of a Tension Leg Platform with a s ingle tendon undergoing planar motion are presented. The huh is represented by a rigid cylindrical body and the tendon as a nonlinear elastic beam. Te ndons have often been modeled as massless springs, which neglects contribut ion to the response by the wave forces on the tendons and its varying stiff ness due to changes in its tension. The structure is subjected to random wa ve loading. Linear wave theory is applied and the random wave height power spectrum is transformed into a time history using Borgman's method. The sur ge and pitch responses for the hull, and the surge response along the tendo n are presented for two cases. Case I represents a tendon with a hull mass two orders of magnitude smaller than the tendon's mass. In Case 2, the hull mass is two orders of magnitude greater than the tendon. Inclusion of tend on forces were found to significantly increase the amplitude of the surge r esponse for Case 1 but not for Case 2. (C) 1998 Elsevier Science Ltd. All r ights reserved.