Insulation of Concrete Bridge Decks

The complete elimination of snow and ice from principal highways would dispel the last real impediment from winter-time driving. It is not possible, of course, to prevent rain and snow from falling onto the roadway nor to heat endless miles of roads in order to keep them snow-and ice-free. Applications of de-icing salts during the onset or following icy weather has become a standard practice since 1948, and the quantity of salt used for this purpose has increased steadily each successive year. At the present time, salting provides the most expediently satisfactory treatment for icing conditions. Bridges sometimes pose a rather special problem inasmuch as they are more exposed and tend to ice prematurely--that is, before the condition prevails elsewhere or throughout the roadway. This poses a rather serious hazard for unwary motorists who are traveling confidently upon a wet pavement and who suddenly find themselves confronted with a dangerous, icy, or frosty bridge. Warning signs and caution lights are sometimes installed at critical locations. Because bridges tend to respond more readily to changes in air temperature, they experience more severe temperatures than pavements resting directly on earth and appear to suffer commensurately greater damage from winter freezes.