Open AccessPILES BEARING CAPACITY IN PERMAFROST SOILS UNDER CLIMATE CHANGE
Author(s) -
Н. С. Никифорова,
A. V. Konnov
Publication year - 2021
Publication title -
construction and geotechnics
Language(s) - English
Resource type - Journals
eISSN - 2687-0908
pISSN - 2687-0894
DOI - 10.15593/2224-9826/2021.3.02
Subject(s) - permafrost , bearing capacity , soil water , environmental science , climate change , settlement (finance) , pile , geology , physical geography , geotechnical engineering , hydrology (agriculture) , soil science , geography , oceanography , world wide web , computer science , payment
The one of the main natural systems in the Russian Federation that are exposed to global warming is the permafrost zone. The temperature of permafrost soils changes, the seasonal thaw zone increases, the process of permafrost degradation is started, influencing the strength characteristics of the soils. The study was aimed to assess the climate change in terms of the impact on the bearing capacity of the soil base under buildings and structures built in the 1960s and 1980s on the Principle I (maintaining the permafrost state of the soil). On the basis of published archival and forecast data on the increase rate in the active layer thickness and the rising temperature trends of permafrost soils for seven geographical regions of Russia (North of the European part, North of Western Siberia, Middle Siberia, Yakutia, Southern Siberia, Baikal region and North-East of Russia) a reduction in the bearing capacity of the standard reinforced concrete pile (35´35 cm section, 10 m long) was determined. The study revealed that for now in most regions the reduction in the bearing capacity of the pile is on average level (10-20 %). However a high (>30 %) decrease is expected by 2050. The temperature distribution in the soil mass was modelled in the Frost 3D program for the conditions of Norilsk, considering the thermal influence of the building. Numerical modelling was performed for a period of time until the middle of the XXI century. In the base of a building the resulting significant settlement of the thawing soil under its own weight can lead to the occurrence of negative friction forces. This effect must be taken into account when calculating pile foundations.