The methods are described in the book of D.Sc. A. Gerasimov “Foundations in Permafrost” (sections 8 - 17) and in the other publications:
https://sites.google.com/site/permafrostfoundations/english-version
An enhancement of design bearing capacity of the columnar and pile foundations on permafrost can be achieved usually by the following means:
- considering the variability of permafrost temperatures, rheological properties and the external loads and actions;
- using means of optimizing the piles cross-section shape;
- applying progressive technological decision of foundations arrangement including use the composition of the mortar poured down pile boreholes;
- by change in the metal and ferroconcrete piles lateral surfaces condition, and by special sand bed under foundations;
- by application of seasonally operating cooling devices.
Settlement reduction of foundations on permafrost ground is achieved by the specified above means. Besides, it is possible to take into consideration at designing the following rated techniques:
- using rigorous nonlinear methods of settlement analysis;
- taking into strict account for columnar foundations a greater effect of their undercutting in ground; the analysis of settlement caused by the creep of frozen soils is conducted in this case by considering the factors reflecting the stress-strain state below the foundations and their actual footing depth.
The bearing capacity enhancement effect may rise to 300% at the load and soil temperature variability considered, and to 200% - due to structural and technological know-how. The base settlement reduction effect may constitute approximately from 50 to 200% depending on the foundation footing depth.
Comments are represented through the author e-mail on the website: https://sites.google.com/site/permafrostfoundations/english-version
