Steel sheet piles are widely used in permanent earth retaining and structural foundation works. In the majority of circumstances, they can be used in an unprotected condition, such conditions are when the steel piles does not required any coating or cathodic protection system to be protected and depends solely on the corrosion allowance calculations The degree of corrosion and whether protection is required depends upon the working environment - which can vary even within the same project location.
In general, marine environments are the most corrosive and unpredictable. In the few meters of vertical zoning which most structures encompass, parts of the sheet piles are in contact with soil, and exposed to seawater immersion, inter-tidal, splash and marine atmospheric environments.
Product Number:
MECC23-19890-SG
Author:
Ahmad Moustafa Rajab
Publication Date:
2023
$20.00
$20.00
$20.00
Cathodic protection can be applied to any metallic structure in contact with an electrolyte. In practice its main use is to protect steel structures buried in soil or immersed in water. The cathodic corrosion process is usually the polarization of all noble potential areas (cathodes) to the most active potential (anodes) on the metal surface and It cannot be used to prevent atmospheric corrosion. Structures commonly protected in offshore area are the exterior surfaces of pipelines, ships’ hulls, jetties, foundation piling, and steel sheet-piling and offshore platforms.
One method cathodic protection may be achieved is by means of the sacrificial anodes systems which use the galvanic series of metals. Sacrificial anode systems have the advantage of being simple to install, independent of any source of electric power, suitable for localized protection, less liable to cause interaction on neighboring structures.
The current density required to maintain the protection potential is very dependent on local conditions. Increased availability of oxygen at the surface of the metal will directly increase current density. Thus, current densities to structures in seawater are likely to vary continuously. The pH of the environment will also be important. The presence of coatings, marine fouling, and calcareous deposits will have a profound effect on current density.
This paper will discuss the cathodic protection design, installation Procedures and commissioning of 2.4 Km of sheet piles with different lengths using 641 kg Aluminum anodes.
