Selecting large diameter piles presents challenges, particularly when it comes to setting out errors. Any misalignment during installation can have severe consequences for the overall foundation stability and load-bearing capacity. Additionally, from a cost perspective, achieving the same load capacity with a group of smaller diameter piles is often more economical than using a single large diameter pile.
Conversely, mini-piles, with their smaller diameters, offer distinct advantages in situations with limited headroom or restricted space. Their compact size allows for easier maneuverability and installation in confined areas. However, for structures requiring only a few piles, the use of mini-piles can be uneconomical due to their higher mobilization costs. As Dr. Edmund C. Hambly noted in 1979, the specialized equipment and techniques required for mini-pile installation can drive up expenses, making them less suitable for projects with a limited number of piles.
Therefore, the choice between large diameter piles and mini-piles involves a careful evaluation of various factors, including site constraints, cost considerations, and the required load-bearing capacity. In scenarios with ample space and a need for high load capacity, large diameter piles may be preferable. However, when space is limited or only a few piles are needed, mini-piles might offer a more practical and efficient solution, despite their higher mobilization costs.