The helical pile is a widespread and competitive technical solution that allows foundations to be built quickly, at low cost and with a low impact on the site, making them economically and environmentally interesting. This solution offers good structural resistance to tensile, compressive and lateral forces. As with any civil engineering structure, its design is of great importance and several parameters influence its bearing capacity. Many studies have shown that the compressive capacity of helical piles varies with the number of helices, their spacing, diameter, angle and position. These studies were carried out in dry sand, and it is known that the presence of water and air in a granular medium, such as in coastal areas, changes the cohesion of the grains, which has an impact on the bearing capacity of the soil. In our study, we propose to focus on the geometric parameters of helical piles and their influence on the behavior and bearing capacity in the case of partially saturated sands. In addition to a literature review of existing analytical approaches, we develop an experimental study in the laboratory, using small-scale 3D printed specimens in a glass bead bed. The aim is to identify the effect of water in the soil-structure interaction in order to propose new relationships that will allow the optimization of the bearing capacity of helical piles during design