Deicing salts effects

In the modem age, a highly developed infrastructure is essential for economic growth and prosperity. Many stmctures essential to this infrastmcture, especially those made of reinforced concrete, have suffered severe degradation since their construction due to the combined effects of deicing salts, freeze-thaw cycles, aggressive environments, and drastically increased live loads. One of the major problems facing the civil engineers of today is to preserve, maintain, and retrofit these structures [1],... 

The corrosivity of the local environment will strongly affect the corrosion performance of the vehicle (19,20). In locations where corrosive environments are possible because of acid rain, deicing salts, or marine environments, personal driving habits and diligent maintenance of the vehicle, such as regular washing and replacement of fluids, can have a significant effect on the reduction of corrosion. 

Corrosion of automobiles is well documented (49-51). Environmental factors such as the deicing salts on the roads and temperature fluctuations have profound effects on automobiles. The cars are expected to survive the grinding effect of gravel, offer comfortable proteetion to the passengers, should be easily and economically repairable on damage with a reasonable service life. 

One of the biggest causes of corrosion of steel in concrete is the use of deicing salts on our highways. In the United States approximately 10 million tonnes of salt are applied per year to highways. In the United Kingdom 1-2 million tonnes per year are applied (but to a proportionately far smaller road network). In continental Europe the application rates are comparable, except where it is too cold for salt to be effective, or the population density too low to make salting worthwhile (e.g. in northern Scandinavia). However, research in the United States has shown that the use of deicing salt is still more economic than the alternative, more expensive, less effective deicers (Transportation Research Board, 1991). 

Corrosion resistance. FRP materials can resist corrosion effects of deicing salts and corrosive chemical environments this resistance provides long life and low maintenance. 

Figure 9.19 Results of a study investigating the transport and effects of deicing salt-laden aerosols.

Bubeck, R. C., and Burton, R. S. (1989). Effect of Decreased Use of Road Deicing Salts (1974-1984) on the Chloride Concentration, Mixing and Stratification of Irondequoit Bay, New York. Water Resour. Invest., U.S. Geol. Surv. Rept. WRI 87-4223, 52 pp. 

Ludwig, U., and Balters, U. (1994). Effect of Cement Type and Quality on the Freeze-Thaw and Deicing Salt Resistance of Conrete. Hochsch. Archit. Bauwes. Weimar Univ, 40(5-7), 133-137. 

Highway. Rock salt, solar salt, and in some cases in Europe, evaporated salt are used to maintain traffic safety and mobiUty during snow and ice conditions in snowbelt regions throughout the world. Sodium chloride melts ice at temperatures down to its eutectic point of —21.12°C. Most snowstorms occur when the temperature is near 0°C, where salt is very effective. More than 40% of dry salt produced in the United States is used for highway deicing. 

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