REPRODUCTION ANALYSIS OF SHAKING TABLE TEST ON MONOPILE TYPE FOUNDATION OF OFFSHORE WIND TURBINE WITH UNDERWATER SEISMIC CONTROL PLATE

Abstract

 The authors have proposed a structure in which a larger cylindrical underwater seismic control plate is partially submerged in water around the monopile foundation of an offshore wind turbine to reduce the cross-sectional force of the MP (hereinafter referred to as "MP") by the interaction between the seismic control plate and water when the MP and the seismic control plate vibrate horizontally when subjected to external forces. Although it has been confirmed from shaking table tests using an underwater seismic table that the cross-sectional force acting on the MP is reduced, a quantitative evaluation method for the resistance due to water, which is considered to be one of the seismic control mechanisms, remains an issue. In this study, the external force due to water was expressed by the Morrison equation, and the damping term of the equation of motion was modeled simply by using damper elements to reproduce the results of shaking table tests using a beam-spring model. The results of the analysis confirmed that the modeling method using the Morrison equation was generally able to reproduce the experimental results.