Numerical Simulation of the Seismic Response of a Horizontal Storage Tank Based on a SPH-FEM Coupling Method

A coupled numerical calculation method combining smooth particle hydrodynamics (SPH) and the finite element method (FEM) was implemented to investigate the seismic response of horizontal storage tanks. A numerical model of a horizontal storage tank featuring a free liquid surface under seismic action was constructed using the SPH- FEM coupling method. The stored liquid was discretized using SPH particles, while the tank and supports were discretized using the FEM. The interaction between the stored liquid and the tank was simulated by using the meshless particle contact method. Then, the numerical simulation results were compared and analyzed against seismic simulation shaking table test data to validate the method. Subsequently, a series of numerical models, considering different liquid storage volumes and seismic effects, were constructed to obtain time history data of base shear and top center displacement, which revealed the seismic performance of horizontal storage tanks. Numerical simulation results and experimental data showed good agreement, with an error rate of less than 18.85%. And this conformity signifies the rationality of the SPH-FEM coupling method. The base shear and top center displacement values obtained by the coupled SPH-FEM method were only 53.3% to 69.1% of those calculated by the equivalent mass method employed in the current code. As the stored liquid volume increased, the seismic response of the horizontal storage tank exhibited a gradual upward trend, with the seismic response increasing from 73% to 388% for every 35% increase in stored liquid volume. The maximum von Mises stress of the tank and the supports remained below the steel yield strength during the earthquake. The coupled SPH-FEM method holds certain advantages in studying the seismic problems of tanks with complex structural forms, particularly due to the representation of the flow field distribution during earthquakes by involving reservoir fluid participation.