Study of bearing capacity of tubular piles with diaphragm under pressing loads

Marine structures often include steel tubular piles of essential length (80-100 m and more) that should provide high bearing capacity in case of external axial loads application. One of the interesting peculiarities of long tubular piles' behavior is the formation of soil plug at the piles' tip. To increase piles bearing capacity under static pressing load, such an additional element as the internal diaphragm has been applied in some practical cases. Presented research aimed to study two connected processes during steel tubular pile driving: soil plug formation at the tip of the open-end pile and soil behavior under the internal diaphragm fixed inside the tubular pile's shaft. Obtained results of internal diaphragm application may be useful to provide an increase of pile's bearing capacity (in case of bearing capacity deficit) or to justify pile length reduction.