Promising Screw Piles Designs for Construction on Permafrost Soils

Abstract

Promising designs of screw piles with improved technical characteristics have been developed, which reduce risk of buckling from soil as a result of influence of tangential forces of frost heave, reduce energy consumption when screwing piles into the soil, and also simplify designs and manufacturing techniques of blades. Usage of cryophobic coatings applied to trunk part placed in the active soil layer is proposed to reduce bulging of piles. Applying anti-friction coatings to the blades, as well as usage of greases filling slots at their edges is proposed to reduce friction when tightening. Strengthening adhesive interaction between pile and soil below active layer can be achieved by applying cryophilic coatings and freezing water in gap between pile shaft and soil. Simplification of pile design is assumed by replacing screw blades with segmented or cable blades.