Installing a Duktus pile

Duktus piles

Material and general information

Duktus piles are pipes made from ductile centrifugal-cast iron with conical sockets and spigots. The GGG 40 material used to make the pipes possesses excellent strength characteristics.

Wheras in cast iron with lamellar graphite the stress lines become highly concentrated at the tips of the graphite lamellae, in ductile iron they flow round the graphite which has separated out in spheroidal form almos udisrupted.

During the pile driving process, the easy-to-join pipe elements form a rigid, tension-resistant and pressure-resistant connection.

Depending on the ground conditions and the construction site requirements, the pile may be used as an end-bearing pile or as a skin friction pile.

Technical values and performance

Tensile strength Rm min. 420 N/mm2
0.2%% yield strength Rp: min. 320 N/mm2
Elongation at fracture: min. 10%% real 15-20%%
Elastic modulus: approx. 170,000 N/mm2
Pressure resistance: approx. 900 N/m2
Hardness: max. 230 HB
Density: 7.05 kg/dm3
Thermal elongation: 0.0118 mm/mK


Pile sizes


118      7.5 mm
118      9.0 mm
170      9.0 mm
170    10.6 mm

Load-bearing capacity

Permissible working load per pile:

Pile PT 118 mm: 520 - 855 kN
Pile PT 170 mm: 910 - 1390 kN
As applicable for pipe wall thickness and design, depending on local substrate conditions

Pile systems

There are two methods for manufacturing Duktus piles:

End-bearing pile

The Duktus pile can be manufactured as a conventional finished ramming pile. The load-bearing capacity is attained when the pile is installed on hard (load-bearing) layers (e.g. on rock).

Friction pile

Pressure-grouted pile

In large-grain substrates (gravel), the load-bearing capability of the pile is attained by using concrete to grout the pile skin. The concrete grouting process significantly increases the pile’s load-bearing capacity in large-grain substrates.

Non-grouted pile

The load-bearing capability of the pile is attained as a result of the skin friction between the pile and the substrate. This design is primarily used in fine-grain substrates (silt, sand). Resistance equals safety!

If you have any questions or would like further information, please do not hesitate to contact us.