Helical metal pile shaft capacity prediction in clay soil

The paper presents the results of experimental studies of the clay soil behavior along the helical pile shaft, which is intended for the foundation of prefabricated and temporary buildings. The tests were carried out on an experimental site, composed of clay semi-solid consistency. A metal single-bladed helical strain gauge pile (tensopile) with a length of 2.5 m and with a shaft diameter of 0.108 m was used in the experiment. Experiments have shown that the bearing capacity of the clay soil along the pile shaft does not exceed 10 % of its total bearing capacity Fd. It has been experimentally identified that the helical pile bearing capacity Fdf is considerably less than the calculated values estimated in accordance with the current regulatory documents. During designing pile foundations this leads to lowering of the depth of helical piles installation and may cause the need to increase the length during the construction or reconstruction of buildings and structures.