Friction pile capacity in soft, fine-grained soils: Two case studies

The ultimate resistance of piles terminating in soft soils is a challenge to predict. Assigning the appropriate soil parameters, tempered with good engineering judgment, is imperative in arriving at a reliable estimate of capacity and pile length. The use of full-scale pile loading tests is also critical in ascertaining the allowable load of a friction pile. This paper presents two case studies containing several pile loading test results. These piles terminated in relatively soft soils, where end bearing was not relied upon. Initial ultimate resistance estimates are possible in advance of the loading tests by carefully considering the soil parameters during the design phase. With care and the use of pile loading tests, it is possible to corroborate the initial ultimate resistance estimates and to demonstrate the capacity of a pile terminating in soft, clayey soils.