THE SILESIAN UNIVERSITY OF TECHNOLOGY
DEPARTMENT OF CIVIL ENGINEERING
REPORT
Corrosion of Steel in Concrete
Person |
Group |
Semestr |
Date |
1. Maciej Pilch |
C |
I |
20 X 08r. |
2. Zofia Oślizło |
|
|
|
3. Krzysztof Konopna |
|
|
|
4. Paweł Melaniuk |
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1. Examined metal: stainless steal, density:
, area:
2. Corrosion environment:
Solution A: sulfuric acid
Solution B: lime water
3. Measure performance:
Item |
No |
Sample characteristics |
Corrosion rate calculation |
||||
|
|
Exposure time T [min] |
Sample mass |
Mass loss WL: [g/m2*day] |
Corrosion rate CR [mm/year] |
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|
Mass before test mb [g] |
Mass after test ma [g] |
Mass difference W [g] |
|
|
1. |
8 |
15 |
6,6881 |
6,6819 |
0,0062 |
0,0161 |
0,0460 |
2. |
33 |
15 |
5,5184 |
5,5087 |
0,0097 |
0,0253 |
0,0719 |
3. |
14 |
30 |
5,5551 |
5,539 |
0,0161 |
0,0839 |
0,2387 |
4. |
47 |
30 |
6,2793 |
6,2636 |
0,0157 |
0,0818 |
0,2328 |
5. |
18 |
45 |
5,7433 |
5,7159 |
0,0274 |
0,2141 |
0,6094 |
6. |
61 |
45 |
5,2668 |
5,2534 |
0,0134 |
0,1047 |
0,2980 |
7. |
5 |
60 |
6,1985 |
6,1719 |
0,0266 |
0,2771 |
0,7889 |
8. |
43 |
60 |
6,3797 |
6,3439 |
0,0358 |
0,3729 |
1,0617 |
9. |
19 |
60 |
5,9887 |
5,9891 |
-0,0004 |
-0,0042 |
-0,0119 |
10. |
24 |
60 |
5,2122 |
5,2125 |
-0,0003 |
-0,0031 |
-0,0089 |
4. Prepare chart:
To prepare those diagrams we need additional table with some average values of samples taken out in the same time. This table will be the base for our diagrams:
No |
Item |
Exposure time T [min] |
Average mass difference [g] |
Average mass loss [g/m2*day] |
Average corrosion rate [mm/year] |
1. |
8, 33 |
15 |
0,0080 |
0,0207 |
0,0589 |
2. |
14, 47 |
30 |
0,0159 |
0,0828 |
0,2358 |
3. |
18, 61 |
45 |
0,0204 |
0,1594 |
0,4537 |
4. |
5, 43 |
60 |
0,0312 |
0,3250 |
0,9253 |
5. |
19, 24 |
60 |
-0,0004 |
-0,0036 |
-0,0104 |
1. W = f(T)
2. WL = f(T)
3. CR = f(T)
5. Conclusions
- Acid environment foster corrosion, significant difference in mass was discovered among samples placed in sulphuric acid solution.
- Alkaline environment protect metal against corrosion, no significant difference in mass was discovered among samples placed in lime water solution.
- Acid rains and contaminated environment can limit lifetime of rebars, and other metal structures
- Corrosion of metal outcome gradually, its tempo is unstable, firstly it's relatively slow, but when metal pore solution pH is nearly neutral, it's starting to increase.
4
Date of laboratory practise: 20.10.08
Lecturer: mgr inż. Anna Kowalik