Concrete Pressure Pipe Provides Long-Term Reliable Service — Even in Adverse Environments
Concrete Cylinder Pipe has consistently demonstrated longevity and reliability when properly installed in most natural environments. The high alkalinity of hydrated portland cement (typically ranging from 12.5 to 13.5 pH) allows for the natural formation of a protective oxide film that is maintained on the embedded steel surfaces and prevents electrochemical corrosion except in extremely adverse environments.
When CPP must be placed in adverse environments, precautionary measures may be necessary to ensure pipeline integrity. The following table identifies various conditions which may require additional measures to minimize the possibility of corrosion.
| CONDITION | CRITERION/CONCERN | POSSIBLE SOLUTIONS (only one solution required) |
|---|---|---|
| High Chlorides in Soil | < 1500 Ω-cm and CI- > 400 ppm |
|
| Stray Current | Anticipated/exists |
|
| High Sulfates in Soil | SO42- < 2000 ppm |
|
| SO42- > 2000 ppm |
|
|
| Severe Acid Conditions | In granular soils, pH < 5, and total acidity > 25 meq per 100 grams soil |
|
| pH < 4 |
|
|
| Atmospheric Exposure | Large temperature fluctuations Wetting & drying cycles Solar radiation Atmospheric carbonation Freezing & thawing |
|
| Connection to Other Pipe Materials | Disparate galvanic potentials |
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Note: This matrix is intended to provide general guidelines for mitigating the effects of corrosion on concrete pressure pipe. Before making any design decision, you should consult your local manufacturer. To find a manufacturer in your area, contact ACPPA.