SIMULATION OF WAVE AND CURRENT FORCES ON TEMPLATE OFFSHORE STRUCTURES
Keywords:
Offshore structures, wave and current forces, Airy , s linear theory, Stokes , fifth order theory, Morison equation, computer programAbstract
This paper describes the analytical and numerical methods adopted in developing a program for modeling wave and current forces on slender offshore structural members. Two common wave theories have been implemented in the present study, namely Airy , s linear theory and Stokes , fifth order theory, based on their attractiveness for engineering use. The program is able to consider wind drift and tidal currents by simply adding the current velocity to the water velocity caused by the waves. The Morison equation was used for converting the velocity and acceleration terms into resultant forces and was extended to consider arbitrary orientations of the structural members. Furthermore, this program has been coupled to a 3-D finite element code, which can analyze any offshore structure consisting of slender members. For calibration and for comparison purposes, the developed programs were checked against a commercial software package called Structural Analysis Computer System (SACS). From the simulations of wave loading and structural analysis on few model tests, it can be concluded that the developed programs are able to reproduce results from the model tests with satisfactory accuracy.
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