Numerical Analysis Based On Vector Form Intrinsic Finite Element-Spring Collision Theory

The Vector form intrinsic finite element method(VFIFE)is an innovative method that proposed by E.C.Ting.The VFIFE method use Newtonian mechanics as a control equation,combining with the concepts of vector mechanics and numerical simulation.It is an efficient method to solve nonlinear problems such as fracture behaviors and collision problems.At present,the VFIFE-rod method is used to calculate collision problems.However,the result is not accuracy enough because this method do not consider the bending moment.Here proposed a new method called vector form intrinsic finite element-spring collision theory to study collision process between jacket foundations and ships.A numerical simulation for collision analysis is designed,which provides a reference for the anti-collision design of offshore wind structures.The main research of this paper includes following parts:(1)Combining with the VFIFE-beam theory and spring collision theory to derive the VFIFE-spring collision theory.This theory is applied to solve collisions between beam elements,which extends the application range of the VFIFE method and provides a theoretical basis for studying collision behaviors between jacket foundations and ships.(2)Based on the VFIFE-spring collision theory,a numerical simulation method is designed to analysis collision problems between jacket foundations and ships by using MATLAB.To verify the reliability of VFIFE-spring collision theory,the curves of the results calculated by the theory and that by ABAQUS is similar,which verify the reliability of this method.Besides,the calculation time is shorter and the calculation efficiency is higher,showing the advantages of this method.(3)Based on the VFIFE-spring theory and the designed numerical simulation,a jacket foundation is calculated to study impacts on mechanical properties of offshore wind structures under different ship quality,crash speed and crash position.