Interaction of Laterally Loaded Free Head Barrette Pile in Elastic Soils

Barrette piles are usually preferred over circular piles where larger bearing capacity, stiffness, and structural capacity are needed. Currently, design work with such piles is usually made assuming an equivalent circular pile diameter. Previous research did not cover pile-soil-pile interaction among piles with rectangular sections. In this study, the soil is assumed as elastic and the three-dimensional nature of the problem necessitated the establishment of 3D numerical analysis models. Piles are modeled as volume elements so that shape effects are properly studied. In this respect, the effects of cross-section and orientation of piles, spacing between piles, stiffness of the soil, and the magnitude of the loading were investigated on the behavior of group barrette piles. Considering these effects, interaction factors were calculated for different pile orientations in a group. Since barrette piles have rectangular cross-sections, the most important factor in their interaction with each other is the resistance of pile on the direction along which the load is acting on the pile. Circular and barrette group piles have been analyzed under horizontal loads. Analyses results showed that unlike circular piles, which have an equal moment of inertia in all directions the barrette piles were highly affected by loading direction and their orientation inside the group. This study emphasized that it is critical to determine the disposition of the piles considering the loading direction if less interaction among piles is desired.