Research Of Dynamic Response Of Sea Dyke Under Wave Loading

Seawall engineering belongs to town and country's hydraulic hazard resistant and disaster reducing engineering, connected with economy developing and people's life of cities along the coast, and its importance is undoubted. However, by this time, research of dynamic action by wave and dynamic stability of seawall is still on initial step.Firstly, the dynamic response model of seawall and seabed under wave loading and the finite element governing equation considering soil skeleton acceleration item are presented, based on two-dimensional generalized Biot's theory. Combining Newmark method, unconditionally stable implicit-implicit staggered solution is adopted to solve in time domain, and FEM analyzed programme is generated. By a quantity of detailed numerical calculation and analysis, space-time distribution of effective stresses, deformation and evolution of excess pore water pressure are simulated. After analyzing several important factors infecting seawall and seabed and infection degree, some useful conclusions are gained.Firstly by validation and calculation, feasibility of the programme is verified. The programme is utilized to analyze dynamic response of seabed in front of seawall. Then some important factor are discussed and dynamic property related of seabed is summarized.Subsequently, dynamic interaction of the system of wave-seawall-seabed is analyzed. Homogeneous, real soil material and sandy foundation soil are discussed individually, and the condition of wave impact is imitated. It is shown that the difference is obvious for various soil materials. After analyzing dynamic interaction of the upright seawall system, the dike body is always in stronger dynamic action, and not suitable to use frequently.The thesis discusses dynamic stability of the seawall- seabed system primarily. The transient liquefaction discriminant presented by Zen etc. is modified. The research of dynamic stability shows it important to consider excess pore water pressure. By calculation, the possible shear failure plane is depicted. Finally, reinforcement mechanism of the seawall foundation is explored, and improvement methods of dynamic stability of seawall and seabed are presented.