Load Transfer in End-Bearing Steel H-Piles

Pile load tests on instrumented piles reveal that load transfer to surrounding soil is a significant factor in the capacity of point bearing piles. The piles tested were 14BP89 and 14BP117 steel H-piles driven approximately 40 ft through sand and gravel. The piles were point bearing in shale. Such piles are relatively short and stiff, but the tests revealed that they were of sufficient flexibility to transfer approximately one-third of the applied load to the surrounding soil. A theoretical calculation of load transfer is presented and is in good agreement with the observed results. The mechanism of pile failure, and significance of load transfer in the failure mechanism, is described and examined in terms of significance in design.