PILEs in structural foundations that are used to load transmissions from the main structure to the bed are generally subjected to lateral loads. In order to study the effect of concrete PILE geometry on its structural behavior, several models with different shapes and dimensions were selected and analyzed, assuming nonlinear behavior for soil. The behavior of the PILE models was studied, evaluated and tabulated using numerical analysis under different conditions, such as changes in the PILE geometry and shape, and soil properties. Therefore, the DISPLACEMENTS of PILE HEADs situated in granular soil, with different compaction levels, under a lateral load, were studied in loading and unloading cycles. The dissipated energy was calculated based on PILE HEAD DISPLACEMENTS in different load steps in the first and second cycles of loading. The "performance index" is defined as the ratio of dissipated energy to the maximum PILE HEAD displacement, and these two factors effects on different PILE model behavior were compared, concurrently. It was observed that PILEs with rectangular cross sections and smaller width have the maximum dissipation of energy, and the minimum displacement occurs in dense soil.

One of the proposed solutions to strengthen and improve the stability of earth slopes is to use PILEs that will be placed vertically and along the slope in a row. In this research, the parameters affecting the stabilization of soil slopes were investigated using the finite element numerical model with ABAQUS software. The results showed that the location LX/L equal to 0.6 is the most optimal place where the PILE can be placed since the largest DISPLACEMENTS have taken place there. According to the studied numerical models as well as the soil conditions, it can be said that the failure surface does not pass between the two soils and the failure surface remains only in the upper soil area. As the factor of safety increases in models where the PILE location changes, the values of vertical and lateral displacement of the soil increase. In other words, with an increasing factor of safety, the amount of lateral and vertical displacement of the PILE also increases.

Today, ground-source heat pumps (GSHP) are one of the most efficient solutions to reduce energy consumption. Utilizing energy PILEs as a kind of energy geostructure can enhance the cost-effectiveness of projects incorporating GSHP systems. In this study, the ultimate bearing capacity of an energy PILE was compared in the two general base-only-restrained and both-ends-restrained conditions. For each of these two conditions, the relative densities of 48% and 85% and the temperature changes of ΔT= 17 °C and ΔT= 30 °C were regarded as variables. During the test, the soil and PILE temperatures, the PILE HEAD, the PILE tip DISPLACEMENTS, and the thermomechanical strains in a PILE were recorded. These parameters are used for calculating the temperature profile, thermal stresses of the PILE, side shear stresses, and the ultimate bearing capacity of the PILE. The results showed that the increase in relative density and temperature led to an increase in thermal stress and ultimate bearing capacity. The minimum UBC increase was obtained for the base-only-restrained condition with a relative density of 48% and ΔT= 17 °C, which was about 10%, while the maximum increase of 21% was obtained for the both-ends-restrained condition with a relative density of 85% and ΔT= 30 °C.

Nowadays, using the PILE group has special importance due to the transfer of structure load to hard layers of soil or rock. Therefore, any damage to the PILE group can lead to irreparable risks. On the other hand, the importance of explosive loading and the development of passive defence systems require more appropriate measures concerning the effects of explosion loading on the PILE groups. One of the most important parameters in PILE group is PILE space. In this study, the effects of PILE space in the PILE group under explosion loading are investigated. For this purpose, the numerical analysis of the PILE group has been performed using the Abaqus software and by Coupling Eulerian-Lagrange method. According to the results, it was found that increasing the lateral or longitudinal PILE space in the PILE group would improve the condition of the PILE group against the explosive loading.

PILE foundations are widely used to ensure the stability of structures subjected to seismic excitation. Numerous structures and foundations in soil-PILE-structure systems have been destroyed during occurrence of earthquakes. Because of complexities involved in soil-PILE interaction problems and the lack of precise methods, it is necessary to use numerical methods for analyzing soil-PILE interaction problems. There are several factors affecting the dynamic response of a PILE in soil-PILE system. These factors can be divided into three main categories: geometrical factors, material properties, and load characteristics. Studying the effects and importance of these factors in the response of the PILE will help geotechnical engineers to optimize their design. In this research, three-dimensional modeling has been developed using FLAC3D computer program, and the effects of various soil and PILE properties on the dynamic behavior of a single PILE in clayey soils are evaluated. One of the most important subjects in the numerical modeling of soil-PILE system dynamic response is the constitutive model considered for the soil. This strongly affects the accuracy of results. In this study a softening model has been used for the behavior of the soil under dynamic loads. Sinusoidal harmonic loading has been applied to the model base as the acceleration time history, and the variations of bending moments, shear forces, and DISPLACEMENTS along the PILE are obtained for all analyses carried out in this study. The results show that kinematic interaction coefficient depends on the loading characteristics and in the high frequencies HEAD PILE response is lower than free field.

The PILE driving process can be easily modeled prior to installation to determine adequate and appropriate equipment selection. Pre-casted lightweight concrete (LWC) provide an attractive alternative to conventional PILE materials such as steel and common concrete by improving the durability of deep foundations. In this paper, the drivability of cylindrical and tapered PILEs with lightweight concrete was investigated and compared with traditional PILE materials using the finite difference analysis. The three-dimensional model was considered to simulate PILE-soil system in drivability by FLAC3D. The vertical LWC PILE was assumed to behave linear elastic, and the soil was acted in elasto-plastic material obeyed the Mohr-Coulomb failure criterion. Interface elements were also used at the soil-PILE contact surfaces along the PILE shaft and toe to allow the slip occur during the driving procedure. Quiet boundaries were considered to prevent waves traveling in the lateral and vertical directions for the soil. The different concrete mixtures with Leca and Scoria were assumed to compare the size of the physical properties of light aggregate, which letters S and L represent Leca and the Scoria in each concrete mix design.The analysis of wave propagation in LWC rods without and with damping effects were performed with fixed and free end boundary conditions. The rod gravity was neglected with no soil or other supports around the rod shaft. A half-sine stress wave was applied on the rod HEAD. To represent the dynamic responses, the force and velocity records were monitored below the rod HEAD to prevent the mixing up the upward stress wave and downward reflection from the rod HEAD. The obtained results were exactly in accordance with one dimensional wave propagation theory in rods.The immediate F and Z.v waves shifted down after tip reflections are the reflections from the rod free HEAD boundary condition. In fact, the downward initial compressive wave is reflected as compression type at rod fixed-end and reflected tension type at the rod free-top boundary conditions. The F wave and Z.v wave amplitudes were attenuated with time as expected due to the damping presence in the rod.The PILE drivability with light weight concrete and cylindrical and tapered geometry was also investigated in clayey soil and the results were compared.Based on signal matching for LWC PILEs, as expected, residual DISPLACEMENTS of PILE S2 and L3 are 8 to 20% greater than common concrete PILEs, and PILE S3 has approximately the same behaviour as PILE CC.The analyses results indicate that LWS PILEs with selecting the appropriate mixture design and ratio between elastic modulus and specific weight have a better performance compared with common used concrete and therefore, it can affect the PILE optimum penetration and economic saving of PILE driving procedure.