Asymptotic Analysis of TLP Tendons and Risers

Except for the presence of highly localized bending stresses near the supports, the behavior of a slender tendon or riser under axial tension is essentially similar to that of a stretched string. From the viewpoint of analysis, however, a tendon or riser is neither a string nor a conventional beam, thus suggesting the exploration of more suitable analytical techniques. The relative significance of the flexural stiffness of such a slender member can be expressed conveniently in terms of two perturbation parameters, one for each end of the member. Closed‐form asymptotic formulas are developed to depict, in an explicit and quantitative manner, the extent to which static or dynamic behavior of a tendon or riser may be affected by localized bending stresses near the supports. These formulas include, in particular, closed‐form expressions for distribution of localized bending stresses, effect of rotational springs at the supports, lateral vibration frequencies of tendon or riser, and corresponding mode shapes.