A FESEM/EDX investigation into how continuous deicer exposure affects the chemistry of Portland cement concrete

作者：Shi Xianming^*; Fay Laura; Peterson Marijean M; Berry Michael; Mooney Matthew

来源：Construction and Building Materials, 2011, 25(2): 957-966.

DOI：10.1016/j.conbuildmat.2010.06.086

• Deicer
• Portland cement concrete
• FESEM
• EDX
• NaCl
• CaCl2
• MgCl2

This work experimentally investigates how continuous deicer exposure affects the strength and chemistry of Portland cement concrete, by ponding two types of concrete samples under four diluted chloride-based deicers respectively at room temperature for an average of 338 days. The two mix designs investigated represent the roadway pavements and bridge decks built by the Washington Department of Transportation (WSDOT) before 1980s respectively. For the pavement mix, the continuous exposure to three deicers (non-inhibited NaCl, inhibited NaCl and inhibited CaCl2 deicer) led to limited levels of strength gain of the concrete, whereas that to the inhibited MgCl2 led to significant strength loss. For the bridge mix, the continuous exposure to the four deicers led to significant strength loss of the concrete, with the inhibited CaCl2 deicer being the least affected. These results suggest the deleterious role of Mg2+ cations and the beneficial role of Ca2+ cations in altering concrete strength, even though more concrete samples need to be tested in order to validate the findings. The FESEM/EDX data reveal that each investigated deicer chemically reacted with some of the cement hydrates and formed new products, with potential implications on concrete durability. Corrosion inhibitor and other additives in deicers did not show significant benefit in inhibiting the strength or chemical changes of concrete induced by cations and/or anions in deicers. Published by Elsevier Ltd.

• 出版日期2011-2