Dynamic Response Analysis Of Deep-water Piers Subjected To Earthquake And Wave Loadings

For the piers that submerged in deep water, when it suffers the combined effectsof waves and earthquakes, the deep-water pier dynamic response will be affected bythe hydrodynamic pressure on the pier surface. However, there are a fewachievements in this field. In this paper, a new analytical solution is proposed tocalculate the hydrodynamic pressure on the pier, and then study the deep-water pierdynamic response through scaled bridge pier model shaking table test and numericalsimulation. The research work includes the following aspects:(1)After reading the domestic and foreign literature in this field, the method tocalculate hydrodynamic pressure on the pier and the way to analysis the deep-waterpier dynamic response is introduced, at the same time, the main achievements is alsosummarized here.(2)The wave is divided into two parts based on the generation method of waves,the first part is radiation waves which is caused by structure movement, thehydrodynamic pressure caused by radiation waves can be solved by radiation wavetheory; the second part is diffraction waves which come from infinity, thehydrodynamic pressure caused by diffraction waves can be solved by diffraction wavetheory, when calculate the hydrodynamic pressure on the deep-water pier, thedifferent of wave height around the pier is also considered. And then, thehydrodynamic pressure on the model which is be used to test the hydrodynamicpressure by Boo are calculated by the theory proposed in this paper and the FNV(Faltisen-Newman-Vinje) hydrodynamic pressure model, when the result arecompared with the result test from experiment, it find that the formula proposed inthis article is accurate to calculate the first three hydrodynamic pressure on deep waterpier.(3)The test result collected in scaled bridge pier model shaking table test isanalysis, and the relationship between the deep-water pier dynamic response and thehydrodynamic pressure is also investigated here. It finds that hydrodynamic pressureincreases the pier’s dynamic response, and hydrodynamic pressure which is associatedwith the deep-water pier dynamic response changes along the pier height.(4)The ABAQUS user subroutine is developed to exert hydrodynamic pressureon the pier when analyze the model dynamic response by ABAQUS. After comparing the numerical results with the test result, it finds that it is accurate to analyze thedeep-water pier dynamic response through ABAQUS user subroutine to exerthydrodynamic pressure. And then the diffraction wave force is considered whenanalyze the deep-water pier dynamic response.(5)Three actual pier models are established in ABAQUS, after calculating the pierdynamic response, compare the differences of pier dynamic response, it find that thepier geometry, water depth, seismic wave peak, seismic waves are the factors whichaffect pier dynamic response. The pier dynamic response will increase which issurrounded by water, the deeper that pier submerges in water, the more the pierdynamic response will increase; when the seismic wave peak is large, the pierdynamic response is decided by seismic wave, when the seismic wave peak is small,the pier dynamic response caused by diffraction wave is also an important part of thepier dynamic response.