Analysis of the Static Axial Capacity of Helical Piles Using Finite Element Method

Abstract

In the last few decades, there has been an increase in the popularity of helical piles in developed nations and their penetration in the construction field in developing countries. The multiple benefits of helical piles over conventional piles for smaller structures in densely populated or environmentally sensitive areas for both onshore and offshore construction have made it an obvious choice for many geotechnical engineers. Moreover, the development of high torque-generating machines has revolutionized the use of helical piles as their installation process has now become much easier and faster. Therefore, it is important to analyze the behavior of helical piles using modern and sophisticated techniques. Finite element method provides the flexibility of easy analysis of the working mechanism of helical piles by reducing cost, time, and effort and providing accurate results. Finite element analysis (FEA) incorporates more variables such as the stiffness properties, and soil-pile interactions and provides a load settlement curve, thus offering a more realistic result. In this paper, the characteristics and behavior of helical piles under different design parameters, loading directions, and soil conditions have been analyzed using finite element method in Plaxis 2D software. The parametric analysis demonstrates the influence of different design aspects and other conditions around the pile on its load-carrying capacity. The extent of influence zone formed around the pile upon loading and the deformation pattern at failure have been studied. The values of critical spacing ratio and critical embedment ratio have been determined for both cohesive and cohesionless soils.