Pile installation has a great impact on the subsequent mechanical pile response. It is not, however, routinely incorporated in the numerical analyses of deep foundations in sand. Some of the difficulties associated with the simulation of the installation process are related to the fact that large deformations and distortions will eventually appear. The finite element method is not well suited to solve problems of this nature. Hence, an alternative procedure is tested herein, by using the material point method to simulate the installation of statically jacked or pushed-in type piles, which has successfully demonstrated its capacity to deal with this simulation. Two constitutive models were also tested, i.e., the modified Cam clay (MCC) and the subloading Cam clay (SubCam), allowing a clear perception of the great advantage to consider the soil with the SubCam model. The simulations have indeed reproduced some of the important features of the pile installation process, such as the radial stress acting around the pile’s shaft or the shaft’s lateral capacity, among other issues. The numerical results were additionally compared with known (semi-empirical) methods to derive the lateral capacity of the shaft, with a good and practical outcome.

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Brazil has increased the use of renewable energy during the last years. Due to its sunshine and large surface area, photovoltaic panels founded in helical piles have been used to produce solar energy. Since Brazilian territory is mainly cover by highly porous structured tropical soils, when the helical piles are installed this structure is broken and its soil properties are modified. Considering the special characteristics of these soils, helical foundations behavior must be extensively studied. The first objective of this work is to determine the most suitable method to estimate the tensile capacity of helical piles in tropical soils. The second objective is to simulate the behavior of these piles in tropical soil. To obtain the rupture to assess load-displacement curves and the ultimate load, also a numerical modelling using Plaxis software was conducted. Lastly, the ultimate load and the load-displacements curves are compared with experimental values to validate the implemented model.