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 These are the structures, which are concerned by reinforcement corrosion :
 

 Building : acroteria and balconies, in any atmosphere, vertical elements and terraces, in industrial and marine environments are indeed the most sensitive elements in buildings, due to either their thinness, or the difficulty to obtain a cover, which is thick enough.

 Industrial buildings : pillars and slabs are indeed often exposed to chemical agents. Beams in industrial structures are also elements, which are particularly sensitive, as they support some floor slabs. Some of them are sometimes in somewhat surprising conditions.

 Carparks beams and slabs, in marine or mountain sites. The reason in both cases is the presence of chlorides (coming respectively from sea water and de-icing salts). It should be known that many slabs are of prestressed concrete, this increases the risk of corrosion.

 Components of prefabricated structures : it does seem that no significant problems are observed, likely because concrete has then a better making and a better placing. However, some pillars of electrical lines for example seem to be a subject of concern. It should be known that in France the set of reinforced concrete pillars is large (approximately 1 per 2 inhabitant), the oldest of them are more than 60 years old.

A significant pathology also exists concerning various structural components, due to the use, in the 1960s-1980s, of concrete accelerators containing calcium chlorides. This concerns exterior wall panels, acroteria, flowers stand, etc.

 Bridges and structures : in these structures, the most significant zones are decks, supports of superstructures, and deck equipment (where de-icing salts have a significant influences).

 Tanks (buried, on ground, in air). The principal problem for these structures is water leakage, which are due to cracks (of various origins: thermal, mechanical, etc.) or defects of reinforcement cover, mainly if the environment contains aggressive salts (chlorides, in particular).
On existing structures deteriorated by cracks, or diffuse leakage, repairs consist in clogging defects or in sealing.

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  Silos : for storing granular or powdery materials (cereals, cements, etc.) are subjected to strong strains, in particular during loading and of unloading. These strains induce cracks (horizontal or verticals). These cracks can induce water penetration, which initiates reinforcement corrosion.

  Industrial air coolers are subjected to a severe environment (water fog including vapour and droplets inside, and sun, rain or freezing outside) generating constraints starting of the cracks. In addition the strong moisture gradient induces of water vapour transfer, which can be the origin of concrete deterioration.

 Chimneys (particularly, industrial ones) are subjected to a very severe, acid environment (sulphuric and hydrochloric acids). Their barrels are facing phenomena due to the neutralization of concrete alkalinity, on the one hand, and to sulphate attack, on the other hand (by gypsum formation). This attack is sometimes very deep, and often depends irregular on the height.

 Harbour structures on sea shore are under an attack due to chlorides. The corrosion intensity depends on the aggressiveness of the environment (tide, splash, spray zones). Defects in cover failures and concrete quality are then immediately highlighted.

 Reinforced and prestressed concrete pipes : most of them are buried, and ruptures occur when the protection due to concrete is no more sufficient (carbonation, presence of chlorides).

It is also necessary to include historical monuments (churches or other works designed by architects like Perret or Le Corbusier), made of reinforced concrete, with an increasing number, which have their own constraints, in particular concerning their repair.

At last, the internal concrete diseases due to its own components (alkali aggregate reaction, differed ettringite formation, etc.) are particular cases, which induce various damages (cracking, deformation).


 
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