Investigating the Effect of the Type of Mold and the Type of Release Agent on the Bugholes on the Concrete Surface

Document Type : Original Article

Authors

1 M.S.Graduted, in Construction Engineering and Management. K. N. Toosi University of Technology

2 1Associate Professor, Faculty of Civil Eng., K. N. Toosi University of Technology

Abstract

Today, with the progress of the construction industry and the importance of reducing costs, the multi-purpose use of consumables has attracted the attention of builders. Exposed concrete is one of this category of materials, which, in addition to its structural use, also has an architectural function. The use of Exposed concrete requires minimizing bugholes in concrete and achieving appropriate appearance quality. In this research, the effect of the surface material of the mold, including steel and coated plywood, and the type of mold release agent on the bugholes, as well as the amount of staining on the concrete surface, was investigated. the conducted investigation shows that the performance of coated plywood mold is slightly better than steel mold and leads to less bugholes. In terms of the effect of the type of releasing agent, the results show that the mineral-based releasing agent has a better performance in terms of bugholes compared to the organic-based releasing agent in minimum consumption amounts. However if this type of substance is applied in excessive amounts, it leads to staining on the concrete surface, reducing its surface quality. The organic based material did not cause a problem in terms of staining even in high consumption rates.

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References

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History

  • Receive Date: 10 August 2022
  • Revise Date: 04 September 2022
  • Accept Date: 22 September 2022

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