Summary of pile capacity predictions and comparison with observed behaviour

Results of twenty-four a priori predictions of behavior of four piles loaded in axial compression are summarized. The 50-ft-long piles were installed through 23 ft of dense sand and 27 ft of medium stiff clay. An HP section, a pipe pile, and two drilled piers were instrumented and tested 2 weeks, 5 weeks and 43 weeks after installation. Predictions include axial capacity at each test interval, load-deflection response at the pile head, axial load distributions along the pile length, residual stresses during installation and after each load test, pore pressure responses and lower bound estimates of axial capacity. Predicted results are tabulated and compared with observed behavior.