RU128210U1 - SCREW PILES FOR LOOSE SOILS - Google Patents

Abstract

A screw pile consisting of a cylindrical metal pipe with a rigid metal winding on its surface, which is located at the upper end of the pipe and partly at the lower penetrating guide deaf cone, characterized in that the upper winding is 2-2.5 times larger in diameter in diameter, and both windings are conical, and in the center of the pipe there is a metal tube that is plugged within the cone, while through holes are made on the surface of the pipe, which is free from winding, and on the central inner tube at the same levels, increasing diameter from top to bottom along the length of the pipes to exit the injected hardening solution.

Description

The utility model relates to the field of construction, mainly to the use of suspended piles and can be used in the construction of pile foundations in loose soils of high power.

A known design of a screw pile, including a metal pipe with a metal winding placed on its surface along the entire length, and the cone at the bottom, is conical (Patent 2304664 C1, E02D 5/56, RU, 08.20.2007). The disadvantage of this design is the difficulty of its immersion in the soil due to the large area of winding.

Known designs of screw piles constructed from metal strips (patents 2172373 C2, E02D 5/56, RU; 228402 C2, E02D 5/56, RU). Their disadvantages are the complexity of manufacturing and a sufficiently high soil resistance during their implementation and low bearing capacity.

Known designs of screw piles with cylindrical winding and tapered at the lower end (patent 2288326 C1, E02D 5/56, RU). The disadvantage of such piles is the formation of wide (up to 5 diameters of pipe sizes) screw coils in order to increase the bearing capacity, which makes their introduction into the soil difficult.

The closest in technical essence to the claimed utility model is a screw pile, in which an injector in the form of a pipe with holes is attached to a screw conical shoe connected to a pipe inside the barrel for supplying a soil-strengthening mixture (patent 2413818 C1, E02D 5/56, RU). The disadvantage of such a screw pile is the weak design of the injector, respectively, its low reliability against breakage when immersed in the ground.

The proposed solution is aimed at increasing the bearing capacity of a screw pile not only due to friction forces along the screw surface, but also due to an increase in drag forces by forming around the pipe pile a pear-like soil broadening, which is adhesively bonded to the pipe, which is molded by supplying a hardening mortar to the near pile pile soil.

This goal is achieved by using a screw pile, consisting of a metal pipe with a rigid metal winding on its surface in 2-3 turns at the upper cone of the pipe and 5-6 turns at the bottom along the implanting guide deaf cone. At the same time, the upper winding is 2-2.5 times larger than the lower one, and both windings are made with cones. In the center, inside the pipe, there is a metal pipe, which is plugged within the cone, and on the central inner pipe and on the surface of the pipe, which is free from winding, there are made radially and coaxially through holes with increasing diameter from top to bottom along the length of the pipes to exit the hardening solution.

In the upper, above-ground, part of the pipe, below the shank for rotation, a nozzle for the pressure pump hose and a packer, in the form of a pressure washer, are constructed to prevent the solution from breaking to the surface through the gap between the screw winding. The inner and outer surfaces of the pile pipes are coated with an anti-corrosion substance.

The essence of the utility model is illustrated by graphic materials, where figure 1 shows the placement of a screw pile in the ground; figure 2 shows a screw hanging pile and a section along aa. The following notation is used in the figures: 1 - shank for a drill rotary cartridge; 2 - hollow (cylindrical) central pipe; 3 - upper conical screw through the pipe; 4 - lower conical screw; 5 - an internal tube; 6 - holes for the exit of the hardening solution in the inner tube; 7 - hole in the outer pipe; 8 - packer above the screw; 9 - washer; 10 - clamping nut; 11 - pipe fitting for a pump hose; 12 - discharge hose; 13 - soil mass; R is the radius of soil fixation.

The hanging pile is immersed in the ground by rotation through the shank 1, like a drill rod. Then, the discharge hose 12 from the metering pump is connected to the nozzle 11. The supply tank is filled with prepared hardening solution, the volume and time of curing of which is calculated according to known dependencies. During injection, the solution fills the pipe 2 and, leaving the holes, spreads radially from the pile, forming a pear-shaped fixed mass of soil 13, adhesively bonded to the pile, many times increasing its bearing capacity.

The fixing hardening solution can be either based on sodium silicate or on the basis of KFMT low toxicity carbamide resin with an acid hardener (weak hydrochloric or oxalic acid 3-4%) in an amount of 5-10% of the resin volume diluted with water 1: 1 or 1: 0.5.

Thus, the proposed design of a screw pile after injection has an increased supporting surface and a corresponding bearing surface without compromising strength properties.

Claims (1)

A screw pile consisting of a cylindrical metal pipe with a rigid metal winding on its surface, which is located at the upper end of the pipe and partly at the lower penetrating guide deaf cone, characterized in that the upper winding is 2-2.5 times larger in diameter in diameter, and both windings are conical, and in the center of the pipe there is a metal tube that is plugged within the cone, while through holes are made on the surface of the pipe, which is free from winding, and on the central inner tube at the same levels, increasing diameter from top to bottom along the length of the pipes to exit the injected hardening solution.

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