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LPS Concrete MV clamp
Part No. 390 050

Fixed earthing terminal
Perimeter Part No. 478 011
insulation

Cross unit Main earthing busbar (MEB)
Part No. 318 209 Part No. 563 200

Spacer
Part No. 290 001 Floor slab

Blinding layer

Foundation earth electrode Soil

Figure 5.5.2.26 Arrangement of the foundation earth electrode in case of a strip foundation (insulated basement wall) according to the Ger-
man DIN 18014 standard

In Germany, steel fibre concrete is mainly used for industri- the efficiency of the steel fibres used. A static calculation must
al and residential buildings. The steel fibres typically have a be made to select the required type and quantity of steel fibres.
length of 50 to 60 mm and a diameter of 0.75 to 1.00 mm. Since steel fibres do not significantly influence the electrical
Straight steel fibres with hooked ends or crimped steel fibres conductivity of concrete, an earth electrode with a mesh size
are most commonly used (Figure 5.5.2.27). The required con- ≤ 20 m x 20 m must be installed as earthing measure for pure
tent of steel fibres depends on the load on the floor slab and steel fibre concrete slabs. The earthing conductor can be in-
stalled in the concrete and must be covered by a concrete layer
of 5 cm on all sides for corrosion protection reasons if it con-
sists of galvanised material. This is impractical on site in most
cases. It is therefore advisable to install a corrosion-resistant
ring earth electrode made of stainless steel (V4A), e.g. mate-
rial No. AISI/ASTM 316 Ti, below the later foundation slabs. The
relevant terminal lugs must be considered.

5.5.3 Ring earth electrodes – Type B earth
electrodes
The earth-termination system of existing structures can be de-
sign in the form of a ring earth electrode (Figure 5.5.3.1). This
earth electrode must be installed as a closed ring around the
building or, if this is not possible, a connection must be made
Figure 5.5.2.27 Fresh concrete with steel fibres inside the structure to close the ring. 80 % of the conductors of

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