Interaction Between Sulfate and Chloride Solution Attack of Concretes With and Without Fly Ash

In this paper, 2 sets of concrete under attack from erosion solutions of sulfate and chloride salt were investigated. The first set is plain concrete without fly ash addition, and the other set is concrete with 20% and 30% of fly ash addition, respectively. The corrosion solution includes 3 types: 3.5%NaCl, 5%Na2SO4, and a composite solution of 3.5%NaCl and 5%Na2SO4. In addition, 2 corrosion regimes were employed in this study: natural immersion (stored in corrosion solution for long duration) and drying-immersion cycles. The damage process of the 2 sets of concretes was systematically investigated under the above 3 types of corrosion solutions and 2 corrosion regimes. The interaction between sulfate and chloride salt was also quantitatively determined. Experimental results show that a presence of sulfate in the composite solution increased the resistance to chloride ingress into concretes at early exposure period, but the opposition was observed at latter exposure period. For the damage of concretes, a presence of chloride in the composite solution reduces the damage of concrete caused by sulfate. Addition of fly ash may significantly improve the resistance to chloride ingress into concretes and the resistance to sulfate erosion when a suitable amount of fly ash addition and low water-to-binder (W/B) is employed. Studies of the different corrosion regimes indicate that when concretes are stored in corrosion solution for about 850 d, the changes in relatively dynamic modulus of elastically (RDME) could be described by 3 stages: linearly increasing period, steady period, and declining period. Whereas for drying-immersion cycles, an accelerated trend could be found. The changes in RDME included an accelerated decreased stage, linearly increased stage, and then a slowly decreased stage, finally accelerating failure stage. In order to elucidate the above experimental results in a microscopic scale, the mechanism was also investigated by the modern microanalysis techniques.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/00088846
• Supplemental Notes:
  • Abstract reprinted with permission from Elsevier
• Authors:
  • Zuquan, Jin
  • Wei, Sun
  • Yunsheng, Zhang
  • Jinyang, Jiang
  • Jianzhong, Lai
• Publication Date: 2007-8

Language

• English

Media Info

• Media Type: Print
• Features: Figures; References; Tables;
• Pagination: pp 1223-1232
• Serial:
  • Cement and Concrete Research
  • Volume: 37
  • Issue Number: 8
  • Publisher: Elsevier
  • ISSN: 0008-8846
  • Serial URL: http://www.sciencedirect.com/science/journal/00088846

Subject/Index Terms

• TRT Terms: Concrete structures; Corrosion; Corrosion resistance; Corrosion resistant materials; Corrosive materials; Durability; Fly ash; Reinforced concrete; Structural deterioration and defects
• Uncontrolled Terms: Chloride ingress; Sulfate attack
• Subject Areas: Highways; Materials; I32: Concrete;

Filing Info

• Accession Number: 01077059
• Record Type: Publication
• Files: TRIS
• Created Date: Sep 28 2007 8:02AM