In accordance with BS5950, steel sections utilized for piling purposes are categorized as either universal bearing piles or universal columns. The former features uniform flange and web thicknesses, while the latter exhibits variations in these dimensions. Despite this distinction, universal columns can also be employed as bearing piles.
When designing head details for H-piles, three primary scenarios must be considered: compression piles, tension piles, and piles subjected to both bending moment and tension or compression. G. M. Cornfield’s 1968 recommendations offer guidance for each case:
Compression Piles: These piles should be embedded 150mm into the concrete pile cap. Notably, the use of dowels or capping plates for connection is unnecessary.
Tension Piles: Hook-ended bars are welded to the top of the H-piles to ensure secure anchorage and resist tensile forces.
Piles with Bending Moment (Tension or Compression): In this scenario, the embedment depth into the pile cap is significantly increased. Load transfer is achieved through horizontal bars welded to the pile flanges, providing the necessary reinforcement to withstand combined bending and axial loads.
By adhering to these design principles, engineers can ensure the structural integrity and optimal performance of H-piles in various loading conditions. The appropriate head detail selection depends on the specific forces acting on the pile, whether it be compression, tension, or a combination of bending and axial loads.