SCREW PILE Russian patent published in 2006 - IPC E02D5/56 

FIELD: building, particularly to erect load-bearing foundation, to retain installation on ground surface and to drive underwater and ground-surface tunnels.

SUBSTANCE: screw pile comprises metal shaft with helical winding connected to the shaft. The shaft is monolithically formed of reinforced concrete and provided with reinforcement arranged at shaft edge. The reinforcement is made as corrugated metal rods having lengths equal to shaft length. Additional spiral reinforcement is formed along the full shaft length. Helical winding is made as reinforced concrete helical blade and extends for the full shaft length. Helical winding width is equal to 0.5-5 concrete head diameters. The helical winding has conical part located in lower pile part and extending for the length equal to not more than 1/3 of pile length. Triangular metal stiffening ribs are distributed over the full helical blade surface and have bases abutting the shaft and connected with each other and with bases of ribs formed on opposite shaft side. The ribs are welded to additional helical reinforcement. Rib apexes are located at blade edge. Apex of each stiffening rib is provided with metal rod. Metal rods of stiffening ribs are connected with each other by metal reinforcement members embedded in blade edge. Member for keyed pile driving means fixation is installed in upper shaft part. The member is made as reinforced concrete bolt.

EFFECT: increased structural load-bearing ability, simplified structure, accuracy and reliability of screw pile driving, as well as possibility to drive pile in densely built-up areas.

3 cl, 5 dwg