Pyramidal piles represent a very fast method of foundation. It is simple for production, prompt, reliable, statically effective, economically advantageous and well controllable method of foundation of industrial, engineering, public and flat construction facilities.

The substantial characteristic of pyramidal piles is the fact that the foundation ground is during the base structure performance not damaged, not expanding, but to the contrary, effectively compacted. Any handling with earth material is excluded. In the pile surrounding there is a compacted earth zone being formed which is together with the effect of inclined walls of the pile body a guarantee of bearing capacity high values. The sloped pile walls (in contrast with the vertical walls of prefabricated piles of constant cross-section, dug or drilled piles) guarantee reliable influence of skin friction in the process of transferring the load from piles to the foundation ground. The effect of ground compaction becomes evident to the depth of 3 m from the pile footing.

The accuracy in driving the pyramidal piles enables direct anchorage of the upper part of the construction without using any spread footings. In order to achieve high accuracy and bearing capacity it is particularly suitable for foundation process of hall facilities, flat houses, family houses, above-ground reservoirs, gas-tanks, facilities in waste water treatments, above-ground product pipelines, pipeline bridges, high voltage power pylons, electrification masts for railways, trolleybus lines. It is possible to construct fences or anti-noise walls on smaller piles.

The use of an impact pile-driver does not initiate any seismic sine curve of vibrations and it has been successfully used in sloping terrains and blank spaces in the built-up area.

Advantages:

• speed of performance 20–30 piles per 8 hours,
• possibility of foundation on low bearing grounds,
• substantial reduction in the scope of earthworks, no excavation, no earth moving,
• pumping of groundwater, shuttering and sheathing,
• foundation in locations with high groundwater levels and in locations with aggressive groundwater,
• volume of concrete falls to 15–20% compared to the foundation on footings or strips,
• very important is that during driving no damage to the pile heads occurs,
• high accuracy of pile driving, directional ± 50 mm, height ± 15 mm,
• it enables continuous check of the pile bearing capacity just at its driving,
• particularly suitable for sandy and sagging earth.

The factored load of fixed pyramidal piles into a bearing ground reaches, depending on the earth type and the pile length, 800 – 1400 kN. For friction piles it is 350 – 500 kN. The factored load of the pile in horizontal direction at the level of the pile head is, depending on the earth type and the pile length, 100 – 300 kN.

The piles have been manufactured in accordance with the European standard EN 12794+A1 – Foundation piles.
Concrete for piles according to STN EN 206–1–C35/45–XF2XC2(SK)–CL0,4–D 16–S3.
We also possess a formulation for electroinsulating concrete which we are able to make up the piles from (as well as normal foundations), with electrical resistance of 3 000 /m. Such piles are suitable for facility foundation, e.g. in aluminium works but even for the masts of traction lines for one-way traction where this concrete eliminates stray earth currents in the ground.

Geological survey in building construction is carried out using a drilling rig or a dynamic-penetration rig up to the bearing ground (gravel sand, slate, stone). The pile length is by rule designed in such a way in order to reach with fixed piles the drive of 0.5 m in the gravel layer. The geological survey at railways is performed by rule using a dynamic-penetration rig or a georadar at the locations of pile mounting.

The piles are manufactured as:
1) railway piles, with pile head size 550 x 550 mm and footing size 120 x 120 mm. There are 4 nuts with thread M 30 in the span 350 x 350 mm and length (L) 3.5; 4.0; 4.5; 5.0 and 6.0 mounted in the pile head.

2) building piles, with pile head size 500 x 500 mm and footing size 120 x 120 mm and length (L) 3, 4, 5 and 6 m. There are a nut with thread GWH24 mounted in the centre of the pile head for connection, strip and footing reinforcement, etc.

3) stay piles, with pile head size 550 x 550 mm and footing size 150 x 250 mm. There are 4 nuts with thread M 30 in the span 350 x 350 mm. Total length of the pile is 4 m.

The approximate price of construction piles including driving is from 84* per 1 lin.m. of the pile depending on the pile quantity a length. The price for 4 hole piles 550x550 mm, including driving, is 120* per 1 lin.m of the pile depending on the pile quantity and length. The price for transport of piles from the factory to the construction site and for the moving of a driving rig to the construction site should be added to the price.