Resources Recycling (자원리싸이클링)

The Korean Institute of Resources Recycling (한국자원리싸이클링학회)
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A Study on the Application of Recycled Fine Aggregate under Sulfate Environment

  • Lee, Seung-Tae (School of Civil & Environmental Engineering, Kunsan National University)
  • Published : 2007.04.27
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Abstract

The report of an investigation into the performance of mortar specimens made with recycled fine aggregate (RA) exposed to sodium sulfate solution for 360 days is presented in this paper. Mechanical properties of mortar specimens such as visual examination, compressive strength, expansion and mass loss were periodically monitored. From the test results, it was found that mortar specimens with higher replacement levels of Rh exhibited poor performance in sodium sulfate solution. However, compared to mortar specimens without RA, those with lower replacement levels of RA (up to 50% by mass) was more resistant to sulfate attack. Through the x-ray diffraction analysis, it was confirmed that the main products causing sulfate deterioration in RA mortar specimens were the formation of gypsum and thaumasite.

Keywords

References

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