IMPLICATIONS OF TENDON MODELING ON NONLINEAR RESPONSE OF TLP

This paper studies the implication of the tendon modeling on the globa l response of tension leg platforms (TLPs) in general, and on the surg e motion (low-frequency response) and the limits of the tendon forces (high-frequency response) in particular The tendons are modeled as mas sless elastic springs connected to the hull or as flexural beam elemen ts with mass and hydrodynamic forces. For the latter, a complete nonli near large-displacement coupled analysis is performed. The TLP studied is subjected to regular waves with various heights and periods in dif ferent water depths. Among other conclusions, the results show that wh ile the simple elastic spring modeling of the tendons with constant la teral stiffness is satisfactory in computing the surge response (horiz ontal motion) amplitude, the hydrodynamic forces on the tendons are ve ry important in accurately predicting the surge mean value (offset). T he hull setdown (vertical displacement associated with the horizontal motion) also significantly affects the tendon forces, particularly for not very deep water.