The influence of time on the bearing capacity of piles in water-saturated clay soils

Abstract

The change in the bearing capacity of piles over time is an established fact that is carefully studied by many researchers. Depending on the type of soils and their condition, there is both a decrease (in sandy) and an increase (in clay) in the bearing capacity of piles over time. The most effective increase in bearing capacity occurs in water-saturated, clayey soils with the property of thixotropy. The results of experimental studies of soils with piles in natural conditions, carried out with different periods of their rest, are of considerable value in the study of this phenomenon. During the construction of a multi-storey residential complex in Odessa, which began in 2019, it became necessary to increase the load on the pile foundation made of prismatic piles with a length of 16 m and a cross-section of 350×350 mm. According to research in 2019, the bearing capacity of the piles was 1500 kN. In February 2021, static soil tests were carried out with the existing piles from under the grillage of the building, which was installed by 90%, while the bearing capacity of the piles was 1800 kN. Thus, for the period from July 2019 to February 2021, the bearing capacity of C160.35-11 piles at the construction site in water-saturated soils in Odessa increased from 1500 kN to 1800 kN, which is 20%.