Abstract
During the past decade, increasing focus has been placed upon longevity and sustainability of major structures, including bridges; and corrosion resistant reinforcements (CRR) for concrete construction represent an attractive option for achieving this in the case of concrete construction. However, there are many CRR options; and the engineer’s materials selection goal in many instances is to identify the least expensive alloy that will achieve the design life. Such selection is often based on results from accelerated tests. The present paper compares experimental results from relatively short-term exposure of selected CRR in simulated pore water to which chlorides were incrementally added with those from longer-term tests in concrete specimens. In both cases, focus was upon determination of the critical Cl- concentration for corrosion initiation, CT. Alloys studied were 3Cr12 (UNS-S41003), 2101LDX (ASTM A955-98), 2304 (UNS-S32304), 2205 (UNS 31803), 316L (UNS S31603) stainless steels, and two 316 stainless steel clad black bar products, and MMFX-2 (ASTM A1035). Black bar (ASTM A615) reinforcement provided a baseline for comparison purposes. Results from the accelerated, aqueous solution tests failed to correlate with the concrete ones in all cases, and it is concluded that projection of long-term performance of reinforcements should be based on exposures in concrete.
