Static load tests were performed on the pile two hours after driving and after four, sixteen, and twenty-nine months of consolidation and setup. The process of consolidation was essentially completed about twelve months after driving, so that the load tests encompass the complete life of a friction pile in highly plastic clays.Upon completion of the static load tests, the pile was subjected to a number of load variations that included cyclic loading in tension above and below a constant bias until failure was indicated by progressive pullout to large displacements. The pile was then subjected to alternate loading to failure in tension and compression to observe the maximum degree of cyclic degradation. Additional variations included studies of the effect of variations in the loading rate and large-displacement loading in compression to evaluate the end-bearing resistance.At the end of the field test program, load, pressure, and displacement data were recorded during pullout of the pile. Data were recorded for over fifty inches of axial displacement as the pile was removed. No significant losses in capacity were observed during pullout. indicating that temporary overload conditions on tension piles may not result in catastrophic failure, particularly if redundancy is provided.
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