METHOD OF SCREW-LIKE PILE BOTTOM SCREWING DOWN Russian patent published in 2004 - IPC

FIELD: construction of pile foundations for civil and industrial structures. SUBSTANCE: method involves putting pile bottom having cup with square or polyhedral cross section and connected with removable metal tube on soil surface in planned point; fixing removable metal tube at the angle of α to soil surface; passing screwing mechanism formed as power couple of reciprocating hydraulic jacks hung on vehicle through inner gripping sleeve; switching on forward motion regime of one hydraulic jack and reverse motion regime of another hydraulic jack; bringing removable metal tube into rotation in clockwise or counter-clockwise direction; imparting rotational motion to screw-like ferroconcrete pile bottom; feeding lubricating clay pulp beneath sharpened pile bottom end for friction reduction between pile bottom and soil; inserting pile bottom into removable metal tube up to stop; removing metal tube; putting hose of pulp- feeding device into space between pile and soil up to pile lower mark; supplying sand pulp by hose up to full filling of space between pile and soil and pulp rise to soil surface; removing hose without stopping of pulp supply; stopping sand pulp supply; repeating above processes with new pile. EFFECT: increased labor productivity by mechanical aid applying; increased bearing strength. 6 dwg