The foundations supporting super structures have been designed in general to cope with compression. However, transmission line structures and marine platforms must resist cyclic tensile forces due to wind and sea waves. In this study, a. model drilled shaft consisted of a small steel pipe and cement grout was constructed in a small pressure chamber to investigate the behavior of the pile installed in compacted granite soil. The test load was provided in cyclic tensile pattern. In this test, the behavioral difference between a pile loaded in tension on the top and a pile loaded in tension at the bottom was investigated intensively. The load transfer curves obtained from the tests were investigated with changing the confining pressure in the chamber. Strain gages were attached along the surface of the steel pipe. The measured strains from the tests were used to obtain the change of the axial forces along the pile. It is found from the tests that ultimate pullout capacity of the pile loaded at the bottom was greater than that of the pile loaded on the top of the pile. In addition, the β-value calculated from the pile loaded at the bottom was greater than that of the pile on the top. The required vertical displacement measured at the ultimate pullout capacity of the pile loaded on the top was greater than that measured at the ultimate pullout capacity of the pile loaded at the bottom.
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