Civil Engineering Reference
In-Depth Information
into zones which are powered, monitored and controlled independently of
each other. The system is illustrated in
Figure 4.2.
Impressed current cathodic protection anodes
The choice of anode is critical in the design of any cathodic protection
system. For concrete there is a wide range of systems, each with their own
advantages and limitations. Anode types currently widely available are as
follows:
1 Mixed metal oxide coated titanium
a. Expanded mesh (in a concrete overlay on the surface)
b. Expanded mesh ribbon (in slots cut in the surface)
c. Probe anodes (in holes drilled or cored into the concrete)
2 Conductive coatings
a. Organic coatings (paint systems, typically chlorinated rubber or
acrylics)
b. Thermal sprayed metal (usually zinc but titanium has been used)
3 Conductive cementitious overlay (one proprietary system uses nickel
coated carbon fibres in a wet sprayed mortar overlay, for example)
4 Conductive ceramic (non-stoichiometric titanium tube type probe
anodes).
