Basic Study on Chloride Induced Corrosion of Stainless Rebar in Mortar Specimen with Bending Crack
Daishin HANAOKA, Ryutaro NASHIMOTO, Shinichi MIYAZATO, Takashi HABUCHI and Takahiko AMINO
Abstract:The objective of this study is to evaluate the chloride corrosion rate of some stainless rebars in mortar specimen with bending cracks. Especially, the corrosion resistance of 7 Cr bearing rebars having different Cr contents is evaluated. Also, the chloride corrosion rate of Cr and Ni bearing stainless rebars with flaws or welds is evaluated. Therefore, in the specimen exposed to an accelerated chloride environment, the corrosion current of the stainless rebar is measured. In conclusions, the corrosion rate of the SUS304 with flaws or welds is lower than that of the carbon rebar SR235 without flaws or welds. Especially, the Cr bearing rebar whose Cr content is 7% or higher has corrosion resistance that is about 10 times larger than that of the SR235. Also, the Ni or Cr bearing rebar (the Cr content is 11% or higher) has extremely high corrosion resistance to the SR235 in a mortar specimen with bending cracks. Based on the above, it is thought that the rebar containing much Cr will be used under severe chloride environments in the future, by considering LCC (Life Cycle Cost). Key Words:Reinforced concrete, Chloride induced corrosion, Cr or Ni bearing rebar, Bending crack, Flaw, Weld