Seismic Performance of Concrete Reservoirs Considering Soil-Structure-Fluid Interaction under Near- and Far-Field Seismic Excitations

The vulnerability of fluid reservoirs in recent earthquakes and locating of Iran in the Alpine-Himalayan seismic belt and the frequent occurrence of destructive earthquakes, as well as the existence of various faults in our country, results in the safe design and analysis of these structures. Seismic excitations in the near range of the fault have different properties compared to the far fault seismic excitations, such as high-frequency content, long periodic pulses in speed-time history, etc. in the near-fault seismic excitations. Therefore, in the present study, the seismic performance of concrete reservoirs was evaluated by considering soil-structure-fluid interaction under near- and far-fault earthquakes. For this purpose, the finite element method was used for numerical simulation by Abacus software. The nonlinear behavior of the bed and the concrete were modeled with the behavioral models of Mohr-Coulomb and damaged plastic concrete, respectively. The Euler–Lagrange element was used to introduce the hydrodynamic pressure of the reservoir fluid and infinite element was used to prevent reflection of seismic waves and earthquake energy loss in the boundary around the bed. After analyzing the boundary distance sensitivity and dimensional analysis of the elements while validating the simulation of parametric studies, the present study was conducted for variables such as earthquake frequency contents, field earthquake, reservoir geometry, and different bed hardness and practical results were presented by comparing the results.