Impact of the rigid piles on the dynamic response of the soil-inclusions-mattress-slab system under seismic excitations

This paper presents a numerical model of the dynamic response of the soil-inclusions-mattress-slab system under seismic loading, with a particular focus on analyzing the influence of inclusions on the reinforcement system. Three-dimensional finite element numerical models with absorbing boundaries based on the direct method are utilized for this study using Code-Aster software. The analysis accounts for two different types of soil behavior: non-linear elastic and elasto-plastic. Six models were simulated in this study, each varying in the number of inclusions, to investigate how the number of inclusions impacts the overall behavior of the system and the variation in internal stresses and horizontal displacements within each inclusion. The objective of this numerical model is to study the influence of the number of inclusions on the dynamic response of a reinforcement system, for both elastic and elasto-plastic behaviors, using the Mohr-Coulomb criterion. The study's findings reveal that an increase in the number of inclusions leads to reduced stresses and displacements within the inclusions. Moreover, inclusions positioned closer to the perimeter of the inclusion network, farther from the point of loading application, experience lower stress levels and are less prone to displacements compared to those located at the network's center. Regarding the impact of considering elastic or elasto-plastic behavior, the results of elasto-plastic calculation are compared with those of non-linear elastic calculation. The results indicate that assuming elasto-plastic behavior in calculations results in decreased internal stresses rather than an increase in displacement.