| Title |
A Study on the Bond Performance and Anti-Corrosion of Polymer Cement Composites Coated Steel |
| Keywords |
PolymerCement Slurry ; Polymer Dispersion ; Polymer-Cement Ratio ; Bond Strength |
| Abstract |
In recent years, in order to prevent the corrosion of reinforcing bars, the method to epoxy-coated reinforcing bars is widely used because of their superior resistance to corrosion. However, in impact test, the coated bars whose coating thickness is thinner than 250㎛, do not meet the requirement of specification. Polymer dispersions(latexes or emulsions) have been developed and commercialized for cement modifiers, and cement composites materials using the polymer dispersions have been widely studied containing coating of reinforcing bar for field of construction work all over the world. The purpose of this study is to evaluate the bond performance of polymer cement slurry-coated steel such as reinforcing bar and H-shaped steel in cement concrete. The bond between concrete and reinforcing bar is critical to the effectiveness of steel reinforcement. The bond between cement concrete and coated steel was evaluated by pull-out test and compression test that involved measuring the bond strength and compressive strength of each sample. Coated steel using polymer cement slurry which is made from two types of polymer dispersions such as PA and St/BA, is prepared. Each coated steels insert in base concrete for bond strength test and compression test. The others are tested for chloride ion spray and penetration tests.
From the test results, the bond performance of coated reinforcing bar is considerably improved by using polymer cement slurry at surface of steel. This difference of the bond performance is markedly recognized according to types of polymer dispersions and mix proportions. Anti-corrosion of coated steel using polymer cement slurry is improved to a great extent compared to those of plain steel. It is apparent that the choice of types of polymer and cement, hardening state of polymer cement slurry at surface of reinforcing bar before inserting in cement concrete is important to improve the bond strength of coated steel using polymer cement slurry. And it is better to develop the reinforced concrete structures than the method to epoxy-coated reinforcing bars. |