scope:

Reinforced Concrete Cooling Towers and Basins are significant civil structures placed in intimate contact with, in many cases, "aggressive" cooling fluids and potentially harsh environmental exposure conditions. These cooling fluids can include freshwater, brackish/seawater, wastewater or a combination thereof with ambient service conditions ranging from tropical to artic climates. As such, prior to initiating reinforced concrete repairs at a cooling tower, it is important to understand the deterioration mechanisms operating and how best to mitigate the damaging effects, prior to performing repairs and placing them into service. Although outside the scope of this document, many different strategies are available to protect reinforced concrete from chloride penetration, embedded metal corrosion, chemical attack and erosion while the structure is in service. A recommended reference exists that outlines reinforced concrete deterioration mechanisms, various protective strategies as well as additional cited references for specific site conditions. The reference is available from the American Concrete Institute (ACI) in their "Guide to Durable Concrete" as Reported by ACI Committee 201.2R. Whereas this document focuses on the use of cast-in-place and shotcrete repair methods, alternate methods such as bonded fiber-reinforced polymer (FRP) wrap systems are also available. These repair and strengthening systems use FRP composite materials as supplemental externally bonded reinforcement. Use of FRP is beyond the scope of this document. However, ACI440.2R is available for recommendations in engineering and construction of FRP systems for strengthening concrete structures.