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http://dx.doi.org/10.4334/JKCI.2013.25.1.073

Mix Design Conditions at Early Curing Age of PCS-Coating Material Effected on Improvement in Bond Strength of Coated Rebar  

Jo, Young-Kug (Dept. of Architectural Engineering, Chungwoon University)
Park, Dong-Yeol (Korea Institute of Construction Technology)
Kim, Wan-Ki (Dept. of Architectural Engineering, Hyupsung University)
Publication Information
Journal of the Korea Concrete Institute / v.25, no.1, 2013 , pp. 73-80 More about this Journal
Abstract
Polymer cement slurry (PCS) made from organic polymer dispersion and cement has good adhesion to steel, waterproofness and acid resistance due to being of polymer films formed in cement slurry. The purpose of this study is to evaluate the mix design conditions at early curing age of PCS-coating material effected on improvement in bond strength of coated rebar. The test pieces are prepared with two types of polymer dispersions such as St/BA and EVA, four polymer-cement ratios, two types of cement, four coating thicknesses and three curing ages, and tested for the bond strength test. From the test results, in general, bond strength of PCS-coated rebar is better than that of uncoated rebar and epoxy-coated rebar. It is also high bond strength at curing ages of 7-day or less, and coating thicknesses of $75{\mu}m$ and $100{\mu}m$. The maximum bond strength of PCS-coated rebar at curing age of 3-hour is almost same as that of curing age of 1-day and 7-day. The maximum bond strength of PCS-coated rebar with ultra high-early strength cement and St/BA at polymer-cement ratio of 80%, and coating thickness of $100{\mu}m$ is about 1.52 and 1.58 times respectively, the strength of uncoated rebar and epoxy-coated rebar. It is apparent that the curing age, coating thickness, type of polymer and cement are very important factors to improve the bond strength of PCS-coated rebar to cement concrete. We can have basic information that PCS-coated rebar with curing age at 3-hour and coating thickness of $100{\mu}m$ can replace epoxy-coated rebar.
Keywords
polymer cement slurry; bond strength; polymer-cement ratio; curing age; coating thickness;
Citations & Related Records
Times Cited By KSCI : 3  (Citation Analysis)
연도 인용수 순위
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