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Figure 5.5.2.11 Use of dimpled membranes Figure 5.5.2.12 Dimpled membrane

cables or lines, connection components for the foundation of at least 320 kg cement (low-heat cement). A low degree
earth electrode or equipotential bonding must be permanently of concrete shrinkage, the recommended minimum concrete
waterproof or pressure-water-proof. The installer is responsible compressive strength C25/30 and the water / cement ratio,
for the watertightness of the building. which must be below 0.6, are equally important.
The term waterproof concrete is not defined in the latest
concrete production standards. In practice, concrete with a Compared to previous years, moisture no longer penetrates
concrete quality of e.g. C20/25 is used (compressive strength some centimetres into the “white tank”. Modern concretes
2
cylinder / cube in N/mm ). with a high resistance to water penetration only absorb 1.5 cm
The watertightness of concrete mixes depends on the cement of water. Since the foundation earth electrode must be covered
3
content. 1 m of waterproof concrete has a cement content by a concrete layer of at least 5 cm (corrosion), the concrete
Connection for the LPS Pressure-water-tight
wall bushing
Part No. 478 530
Waterproof concrete,
Maximum ground water level compressive strength
≥ C25/30, water / cement
ratio < 0.6*

Connecting clamp
Part No. 308 025
Soil

Foundation slab
Sealing tape Main earthing busbar (MEB) Reinforcement
Part No. 563 200

SV clamp
Part No. 308 229
Corrosion-resistant ring Membrane
earth electrode, StSt (V4A) Functional equipotential
* Zement-Merkblatt H 10: Wasserundurch- (e.g. material No. AISI/ASTM 316 Ti) bonding conductor Blinding layer
lässige Betonbauwerke (www.beton.org)
Figure 5.5.2.13 Arrangement of the foundation earth electrode in case of a “white tank” according to the German DIN 18014 standard

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