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Title |
Durability Evaluation of Ternary Blended Concrete Structures Under Chloride-laden Environment
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Authors |
홍성인(Hong Sung In) ; 김영진(Kim Young Jin) ; 안기용(Ann Ki Yong) |
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DOI |
https://doi.org/10.4334/JKCI.2017.29.5.493 |
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Keywords |
삼성분계 콘크리트 ; 포졸란계열 시멘트 ; 염분침투 ; 내구수명 ternary blended concrete ; pozzolanic binder ; chloride penetration ; service life |
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Abstract |
This study aims to assess the durability of high performance concrete in terms of chloride attack. Concrete mix designs made with ordinary Portland cement (OPC) and pozzolanic binders were carried out on the mortar and concrete specimens. From the results of compressive strength at 28 days of water curing, ternary blended concrete showed 80 MPa, which was two times higher than the case of OPC concrete. From the results of chloride penetration tests, 820 coulombs of total charge passed and 9.86E-13 m2/s of diffusion coefficient were observed using the ternary blended concrete, which are 4~5 times lower than those for OPC concrete. From the results of mercury intrusion porosimetry, the pore size at which the maximum mercury intrusion occurs was two times lower than that for the OPC, implying that more dense pore structure that can resist chloride penetration was achieved in the case of the high performance concrete. Finally, the expected service life, defined by the time at which the concentration starts to exceed the chloride threshold level at the assumed steel depth, was determined based on Fick’s diffusion equation. From this, it was shown that 3~4 times longer service life was achieved in the case of ternary blended concrete, compared with OPC.
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