Research On The Dynamic Response Of The Large-cylinder Shell Structure And Numerical Simulation Of The Stochastic Wave Forces

In the field of harbor and offshore engineering, the embedded large-diametercylinder shell is a new-type structure and being brought into use gradually at present.This structure keeps its stability depending on the effect of fixty by deeply embeddedinto the seabed under the force of environmental loads. At the present time, the issueabout dynamic response analysis on the deeply embedded large-diameter cylindershell both under the random wave forces and in the process of vibration sinking is stillunsettled in the field of engineering, and at the same time the issue is also achallenging study for the numerical simulation of the interaction between wave,structure and seabed. Studies on the structural dynamic response are based on the analysis of therandom wave on the large-diameter cylinder shell. Based on the theory ofmicroamplitude wave potential flow, this paper deduces the transfer function betweenthe wave spectrum and the wave force spectrum which act on the large-diametercylinder shell at first. For the first time, the method of random wave numericalsimulation—linear superposition is introduced into the numerical simulation of therandom wave forces acting on the large-diameter cylinder shell, and by using Jonswapspectrum as target spectrum, the numerical simulation is realized combining withsome engineering. Undoubtedly, in the study on the dynamic response of the large-diametercylinder shell, the research about the interaction between soil and structure is veryimportant. On the base of the ANSYS software, this thesis analyses the interactionbetween soil and structure by second developing contact element. For reviewing theeffects of the contact elements in the coupling system, a finite element model ofsoil-structure coupling system is established contrasting with the model experimentabout the deeped large-diameter cylinder shell. The analysis results have goodagreements with the test datas. Combining with some jetty project, a dynamic finite element model of theembedded large-diameter cylinder shell—seabed coupling system is established, andthe contact element is introduced into this system, and the vibration sinking numericalsimulation of this structure is realized for the first time. The analysis results areconsistent to the spot test datas, and it gives science basises to this structure designand the technical adaptation on the dynamic sinking . Combining with some jetty project, this paper establishes a dynamic finiteelement model of the embedded large-diameter cylinder shell—seabed couplingsystem under the random wave forces and the earthquake loads and the dynamicnumerical simulation is carried out. The anlysis reults showed that the structuredesign is safe and reliable under the two kinds of loads. This research gives a newway on the dynamic anyalsis on this kind of structure under the random wave forcesand the earthquake loads.