Multi-objective metaheuristic optimization for simplified modeling of soil-pile interaction systems under lateral and rocking motions

Abstract

A consistent lumped-parameter model (LPM) is established to characterize the dynamic response of single and group piles in a homogeneous half-space subjected to coupled lateral-rocking vibrations. The proposed model comprises adjustable modules that can adapt to simulate a wide range of pile foundation configurations. This study utilizes a metaheuristic algorithm to solve a bicriteria optimization problem, aiming to determine both the layout and parameters of the optimal LPM. The optimal model is created to approximately reproduce the amplitude and phase angle of a soil-pile interaction (SPI) system undergoing harmonic loadings. Besides, the proposed model using frequency-independent elements allows for rapid computation of dynamic responses in the SPI system. Several analyses in the time and frequency domains validate the performance of the proposed model undergoing forced vibrations and seismic excitations. The analyzed results prove the capability and accuracy of the proposed model in approximating the dynamic responses of SPI systems. The results presented demonstrate the significant potential of the proposed model for dynamic structural analysis, particularly when accounting for structural nonlinearities in the time domain.