How to avoid corrosion risk and achieving durability
There is virtually no limit to design and structural possibilities, when reinforced concrete is used. In the past, however, there was one big but: Because the cement stone reacts with the CO2 in the air, causing the pH-value of the concrete pore water to decrease, the corrosion protection of the normal reinforcement is lost over time and thus begins to corrode. The resulting corrosion products initially cause cracks (possibly accompanied by rust plumes) and later concrete spalling, and finally, reduces the bearing capacity. Usual relatively high concrete coverings usually require large-sized and thus heavy components
The solution: Finding the balance between durability and aesthetics
Today, with the use of reinforcement steel with a higher corrosion resistance, slender constructions or applications with a greater risk for cracking, have become possible. Thanks to the higher corrosion resistance of the steel, exceedingly thick concrete coverage has become obsolete. The minimal concrete cover not only has advantages from an aesthetic point of view, but also means that less concrete and thus less construction weight is required, which reduces transport and handling costs.