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In lining or coating applications using ECTFE, permeability of certain small molecules determines the lifetime of anti-corrosion protection. Small molecules such as H 2 O , O 2 , Cl 2 , H 2 S , HCl , HF , HBr , N 2 , H 2 , and CH 3 OH are relatively mobile in the polymer matrix and lead to measurable effects.
The corrosion resistance and low permeability of polymer concrete allows it to be used in swimming pools, sewer structure applications, drainage channels, electrolytic cells for base metal recovery, and other structures that contain liquids or corrosive chemicals. It is especially suited to the construction and rehabilitation of manholes due to ...
The top image shows asperities under no load. The bottom image depicts the same surface after applying a load. In materials science, asperity, defined as "unevenness of surface, roughness, ruggedness" (from the Latin asper—"rough" [1]), has implications (for example) in physics and seismology. Smooth surfaces, even those polished to a mirror ...
Concrete carbonation can be visually revealed by applying a phenolphthalein solution over the fresh surface of a concrete samples (concrete core, prism, freshly fractured bar). Phenolphthalein is a pH indicator , whose color turns from colorless at pH < 8.5 to pink-fuchsia at pH > 9.5.
In sewerage areas where biogenic sulfide corrosion is expected, acid-resistant materials like calcium aluminate cements, PVC or vitrified clay pipe may be substituted to ordinary concrete or steel sewers. Existing structures that have extensive exposure to biogenic corrosion such as sewer manholes and pump station wet wells can be rehabilitated.
Barrier release agents prevent adhesion by the development of a physical film or barrier between the forming surface and the concrete. Reactive release agents are chemically active and work by the process of a chemical reaction between the release agent and the free limes available in fresh concrete. A soapy film is created which prevents adhesion.
[5] [6] The action of either a tensile stress or a corrosive liquid alone would not be enough to cause failure, but in ESC the initiation and growth of a crack is caused by the combined action of the stress and a corrosive environmental liquid. These corrosive environmental liquids are called 'secondary chemical agents', are often organic, and ...
Magazine of Concrete Research, Vol 45, No. 163, June, 1993, p. 155. Serafini, F.L. Corrosion protection of concrete using a Controlled Permeability Formwork (CPF) system; Proceedings of the International conference Corrosion and Corrosion Protection of Steel in Concrete (Ed R. Narayan Swamy), Sheffield, Vol. 2, 24–28 July 1994, pp. 1114–1131.