Effects of Bleeding on the Corrosion of Horizontal Steel Bars in Reinforced Concrete Column Specimens
The durability of reinforced concrete has proven to be predominantly influenced by its resistance against the ingress of harmful substances such as chloride ions, carbon dioxide and moisture. The corrosion of steel bars which occurs especially in marine environments is likely to be severe, depen...
| Main Authors: | , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Universitas Indonesia
2019-07-01
|
| Series: | International Journal of Technology |
| Subjects: | |
| Online Access: | http://ijtech.eng.ui.ac.id/article/view/2503 |
| Summary: | The durability
of reinforced concrete has proven to be predominantly influenced by its resistance
against the ingress of harmful substances such as chloride ions, carbon dioxide
and moisture. The corrosion of steel bars which occurs especially in marine
environments is likely to be severe, depending on the availability of oxygen
and the moisture consumed by cathodic reactions. This study aims to investigate
the effects of bleeding on the corrosion of horizontal steel bars placed in
reinforced concrete column specimens. The issue was examined through
electro-chemical tests, including half-cell potential, polarization resistance
and corrosion current density, conducted using specimens in which corrosion was
induced via dry and wet (NaCl 10%) cycles. The presence or absence of copper
slag fine aggregate and fly ash replacement was employed as an experimental parameter.
The results suggest that the corrosion of horizontal steel bars in the upper
part of the column concrete specimens was adversely affected, even in the case
of OPC specimens with relatively lower bleeding water. This was attributed to lower
resistance against the ingress of corrosive substances, especially in such
locations. In the case of fly ash mixtures, resistance to corrosion was
significantly improved owing to lower oxygen permeability of less than
1.0×10-11mol/cm²/sec, measured via the cathodic polarization
technique. The replacement of fly ash is effective in facilitating more uniform
quality in the column specimens due to a lower level of bleeding water and
higher resistance to segregation and pozzolanic reactions. |
|---|---|
| ISSN: | 2086-9614 2087-2100 |