METHOD OF CONSTRUCTION OF SCREW-CAST-IN PLACE PILE AND DEVICE FOR CONSTRUCTION OF SCREW-CAST-IN-PLACE PILE Russian patent published in 1997 - IPC

FIELD: applicable in construction of highly efficient foundations and anchor supports from piles of wood-screw type made directly in sedimentary grounds with the help of hollow head with screw projection and tubular bar sunk in ground and withdrawn under the action of rotary forces and axial feed. SUBSTANCE: reinforcement and concrete are supplied through upper hole of tubular bar, and they go out through lower hole when bar is withdrawn from the ground. Concrete is fed by metered portions to monitor the quality of well filling. Well is filled with concrete under gravity and pulse sign-alternating vibrations of tubular bar with observation of full conformity of pile body shape with shape of head. Bulged head of pile is formed simultaneously with pile formation with the use of special part fitted on tubular bar. The device for construction of screw-cast-in- place pile is a change attachment to base machine, for instance, excavator or crane, with high torque drive of simplified design with the use of hydraulic cylinder, ratchet and worm gearing. The device is capable of formation from one operating position of many piles of various length and inclination. EFFECT: higher efficiency. 2 cl, 10 dwg