Archimedean screw for placing concrete in ground for construction of vertical walls in ground with mixed-in-place concrete has single spiral fin with cutouts surrounding circular-section tube

摘要

The MIP (Mixed In Place) concrete may be mixed and forced into the ground by a row of vertical screws (11) with boring crowns (7) on their lower ends. The core of each screw consists of a circular-section tube (2). A fin (1) is wound round the core in a spiral and has a series of cutouts (4-4'') of different shapes in its outer edge (3). The liquid concrete or earth binding material (8) is pumped down the tube and escapes through grooves (9) between the teeth of the boring crown.