• Journal of the Korean Society of Hazard Mitigation
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• v.3 no.3 s.10
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• pp.143-150
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• 2003

Recently, The corrosions of reinforced concrete structures are severe problems of economical social effects. PE-coated bars protecting from corrosion and enhancing durability of reinforced concrete structures are testified to evaluate structural properties. Tests are verified by comparative bending tests of the three type materials of epoxy coating, without coating and pe-coating. Load-deflection relations ate superior in pe-coated bar than any other materials(bare bar and epoxy bar). These are proved bonding properties enhancement by using cement powder.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.3
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• pp.254-259
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• 2001

In order to make clear the resistance of plane nettings u,sed widely in constructing net cages, the resistance R taken by $R=kSU^2$, where S was the wall area of nettings, U the flow velocity, and k the resistance coefficient, was measured in a circulating water channel by using nylon Raschel nettings and PE trawler-knotted nettings coated with anti-fouling paint or not and then the properties of coefficient k were investigated. The mesh size L and the angle $\phi$ between two adjacent bars was given by the function of Reynolds number ${\lambda}U/v$ in the region of ${\lambda}U/v<180$, i. e., $$k=350(\frac{\lambda U}{v})^{-0.25}$$.where $\lambda$ was the representative size of nettings expressed as $$\lambda=\frac{{\pi}d^2}{2L\;sin\;2{\phi}}$$On the other hand, the coefficient k was almost fixed between 92 and 102 ($kg{\cdot}s^2/m^4$) in the region of ${\lambda}U/v{\geq}180$ and varied according to the ratio $S_n/S$ of the total area $S_n$ of nettings projected to the plane perpendicular to the water flow to the wall area S of nettings, i.e., it was given by $$k=98.6(\frac{S_n}{S})^{1.19}$$ regardless of the coating of paint.