COUPLED TRANSVERSE AND AXIAL MOTION OF A COMPLIANT STRUCTURE IN RESPONSE TO VORTEX-SHEDDING LOADS

A compliant offshore tower is modelled as a structure having extensional and transverse degrees of freedom. McIverʹs extension of Hamiltonʹs principle is applied to the system, resulting in coupled non-linear equations of motion, due to the assumption of small strain and moderate rotation. The equations of motion are discretized using finite differences and solved numerically. Several forms for the vortex-shedding load are tested, as well as experimental force data. To better understand the model response, Monte Carlo simulations are performed. The results show the feasibility of the present model for representing the response of a compliant structure subject to transverse loading.