The Standard Penetration testing (SPT) is used to develop soil profiles and engineering properties. The same is employed directly or indirectly to determine the bearing capacity of pile foundations. Certain soils exhibit significant elastic behavior resulting in a small permanent set and consequently produce very high blow counts, does not provide a pile with adequate static capacity and prevent the pile driving process from being completed. Therefore, the engineers redesigned the deep foundation system, whereby the large displacement prestressed concrete piles (PCP's) were replaced with low-displacement steel H-piles. Dynamic pile (i.e., PDA and CAPWAP) load testing was performed during the driving of the 610 mm PCP's, and actual pile capacity was determined during end-of-drive (EOD) and at beginning of restrike (BOR) using CAPWAP procedures. In this paper, ten methods for predicting axial pile capacity are investigated and summarized. The measured pile capacities were compared to the predictive capacities to evaluate which predictive method would be best suited for estimating the pile capacity at site where such difficult soils may encountered. Briaud & Tucker (1984), Decourt (1995) and Shioi & Fukui (1982) methods appear to provide a reasonable estimate of the ultimate bearing capacity with factor of safety ranging from 2.7 to 2.9.

Full text: IJEIR_1596_Final.pdf