Features and purpose of screw pile heads

During the construction of the foundation, among other types of supports, screw piles are often used. The main advantage of this type of pile is its moderate cost. In addition, such supporting elements make it possible to adjust the height of the base of the entire structure and to erect buildings on an area with an inhomogeneous relief. At the final stage of the construction of the foundation, the heads are installed on the upper ends of the supporting structures.

A building element called a head is a metal plate with a short pipe and stiffeners welded to it. The top end of the pile is covered with a head after it is buried. It is attached to the support element by welding or bolting.

The function of the heads is to support the subsequent levels of the superstructure and evenly distribute the load on the foundation from the entire structure. Building plates and beams will rest on the plane of the heads. They can also be used for fixing the timber. In this regard, all supporting elements must be located at the same level relative to each other.

Also, thanks to the installation of an end cap, the degree of corrosion damage to the pile is significantly reduced.

Heads can be of different shapes and types depending on the type and configuration of the piles used in the construction.

End elements are made of high-strength structural steel. For additional protection, the heads are coated with alkyd-based primers.

Types of support elements:

• Screw. Such piles are metal pipes of various diameters with a screw base. When the metal support rotates, it sinks into the ground to the desired depth. To fix the support element, concrete mortar is poured into the cavity of the pipe after deepening. The diameters of such support structures range from 108 mm to 325 mm.
• Bored or concrete base. Installation requires punching the soil with a drill. A reinforcement frame is placed in the recesses and concrete is poured.

Benefits of screw piles:

• hold the structure well during extensive floods;
• can be used for construction on unstable soils and uneven terrain;
• installation of support elements can be carried out in all weather conditions, including frost;
• even distribution of the load from the entire structure, with the exception of foundation overloads and distortions;
• allow for an adjustable rise of the structure above the ground level.

Heads for screw piles have a base in the form of a round short pipe of various diameters.

The pile end members primarily differ in the shape of the top plate. They can be U- and T-shaped.

U-shaped elements have staples on their surface. They are mounted on piles for the subsequent laying of beams or beams on them. Moreover, it is important to choose the width of the brackets that is strictly suitable for the dimensions of the beams.

The second type of head has a completely smooth surface. A tiled grillage can also be laid on it.

The next parameter of the pile caps is the diameter of the plate and tubular base. These dimensions depend on the diameter of the supporting elements installed at the base of the foundation of the structure being erected.

The minimum diameter of the round tube at the bottom of the head is 57 mm. The maximum load that can be placed on such a base is no more than 800 kg. Such thin piles are usually used for the construction of lightweight buildings and structures: garages, sheds, gazebos.

The maximum head base size is 108 mm. It is mounted on a thick and sturdy support. Such structures can withstand a mass of up to 3.5 tons. They can be buried in any type of soil. They are used for the construction of supports for heavy buildings and structures, including bridges.

Also, the headgear can be welded or removable. The first type is attached to the base by welding. Removable end pieces can be bolted.

To make the supporting elements of the same height, they are cut or trimmed. This process is somewhat laborious and requires skill, but still we can do it ourselves.

Stages of work:

• At the beginning, a control support pile should be selected. It is at its height that it will be necessary to orientate itself when correcting the length of other support elements.
• On the rest of the supports, a line is drawn with a marker along which the pipe will be cut or cut. The uniformity of the horizontal line should be checked against a laser or hydraulic level.
• The ends of the support elements are cut with a heavy jackhammer. The cutting line is preliminarily cleaned with a file. The blow is applied horizontally along the upper edge of the pipe.
• You can use a grinder or an abrasive saw to cut the base pipes. The cut is made along the line marked by the marker by moving along the diameter of the base or to the center of the pile.
• Another option for shearing pile ends is using hydraulic equipment. Renting it, let alone buying it, is not cheap. However, this method makes it possible to make a cut very evenly, without damaging or chipping the entire base.

Installation of ends:

• Prepared piles should be cleaned of paint using grinding equipment.
• The head is pushed onto the base. Using a level, you should check its horizontalness.
• The element is pre-welded in 3-4 places by spot welding.
• With a welding machine, the head is welded along the entire circumference. A small area of ​​5-10 cm should be left un-welded. It is necessary for the passage of air and ventilation inside the base pipe.
• The weld seam should be cleaned and painted or primed.

The price for each specific screw pile head can fluctuate significantly. First of all, its cost will depend on the size, quality of the material and the location of the manufacturer. Foreign end pieces are often more expensive due to the manufacturer's costs of transporting their products.

On average, round headgears cost from 200-250 rubles. Reinforced heads of large diameter have a lower price limit of 350 rubles.

For information on how to cut screw piles, see the video below.