The foundation is the foundation of an apartment house, fromHow strong it will be, depends largely on how long this building will remain. The choice of the foundation design in each case is determined by the reliability and durability.
In the low-rise residential construction, foundations on screw piles were well established.
They can be erected in any geographical areas on sites with uneven terrain and complex soils.
What are screw piles?
Screw piles are hollowSteel pipes, one end of which is a sharp tip, equipped with a cutting blade resembling a ship's propeller. The spiral blade when screwing the pile into the ground allows you to screw it as deeply as you please. When the desired mark is reached and the penetration is stopped, the blade prevents the pile from being pushed out and securely fixes it in the ground, creating a solid foundation on which the foundation is erected.
Such design features of screw pilesYou can do without complex lifting mechanisms and build a foundation with your own hands. But it should be noted that the quality of the building depends not so much on compliance with the technology, it is quite simple, how much from the quality of the piles themselves. It, in turn, depends on the quality of the steel and on the shape of the blade. An experienced master can determine it at the first glance at the piles: the screw tip of the correct shape is slightly asymmetric, which allows for easy and smooth entry into the ground. If difficulties arise during the screwing process, caused not by the engineering characteristics of the soil, but by improperly manufactured piles, this may prove to be critical for the future structure, down to destruction.
When purchasing screw piles, check their actual shape and dimensions with those specified in the technical passport. It would be superfluous to ask for a certificate confirming the quality of the piles.
The advantages of foundations on screw piles
Screw piles can be installed as manually,And with the use of technical means, in time it can take only 1 day. Their use allows you to save up to 60% of the cost of traditional foundations. For the construction of light country or country houses of foam blocks or senvich panels is the best option, ensuring the reliability of the design for the next 150 years. Pile foundations that do not violate the integrity of soils have proven themselves on the most complex types, wetlands, clay and watered soils, providing the necessary seismic resistance to buildings and structures. This building material is environmentally safe. The pile structure allows to do without waterproofing and immediately after the erection it can already be loaded, which shortens the construction time, and, therefore, its cost.
The technology of installing screw piles under the foundation
At the preliminary stage of construction worksFoundation on screw piles, you need to draw a drawing, calculate the necessary number of your own and determine how long they should be. To do this, you will need the results of engineering and geological studies of your site, in addition, you will need a topographic scheme, which you make surveyors. It is used to link the layout of the foundation of the future house to the situation on the ground and the pile field is marked. For convenience, the outline of the future structure is divided into rectangles, making it easier to control the correspondence of the markup and the actual location of each pile. It is better to start making the pile field by screwing the piles, which will be in the corners of the planned rectangles, they will play the role of benchmarks for marking the position of the piles inside these rectangles.
Accuracy of marking must be maintained within 1-2 cm, this applies to all linear dimensions, including diagonal ones.
In the planned point, a pile is placed in theVertical position with the sharp end with the screw down. If the piles are short and their length does not exceed 2.5 m, a thick metal rod or scrap is inserted into the technological hole at the top of the pile, which must be lengthened at both ends to create a lever. To do this, use pieces of pipes. For piles longer than 2.5 m, it is recommended to use special extensions, they are worn on top and fixed through coaxial holes. A long piece of pipe is inserted into the loop welded to the extension cord, which will be used as a lever when the pile is wrapped. With these simple tools you can manually install piles, the length of which does not exceed 4 m.
To wrap the pile, it will take effort 3-4A person who, for one turn of a pile around their axis, can slip it by 190 mm. The process of screwing must be constantly monitored with a plumb line. The deviation from the vertical axis should not exceed 1-2 degrees. Twisting continues until the calculated depth is reached, but it should not be less than 1.5 m.
When all the piles are installed, it is necessary to trimThem on one level. For this, the usual geodetic levels and angle grinders are used. In the cut piles, a concrete solution is poured in order to strengthen the strength. When the concrete solidifies, the piles need to weld the heads. After that, with the help of logs with studs or self-tapping screws, all piles are connected to a single pile-screw structure of the foundation.