President, Corrosion Control Engineering Ltd., London, Ontario
Pages: 14 Published: Jan 1990
The state of the art in soil corrosivity testing was evaluated, with particular emphasis on field and in-situ tests that can be performed with reasonable accuracy by nonscientific personnel. Parameters reviewed include resistivity, pH, redox potential, moisture content, chloride levels, structure/soil potential, and microbiological activity. The reliability of in-situ tests versus laboratory tests is examined. Particular emphasis is placed on buried and immersed ferrous materials. A distinction is made between studies intended to determine the soil factors affecting the integrity of intended new installations and studies which examine the condition of the existing facilities and the relationship of soil parameters to structure condition and anticipated life. The latter circumstance is becoming increasingly evident as infrastructure rehabilitation studies focus on the condition and future life expectancy of buried facilities. Several approaches to expected life prediction are reviewed. Emphasis is focused on information presented in ASTM STP 741, Underground Corrosion, and ASTM STP1013, Effects of Soil Characteristics on Corrosion. The applicability of the ASTM Method for Field Measurement of Soil Resistivity Using the Wenner Four-Electrode Method (G 57-78) and the ASTM Test Method for pH of Soil for Use in Corrosion Testing (G 51-84) is considered. The available information is consolidated into recommended practices for soil corrosivity evaluations.
soil corrosion, ferrous materials, parameters, resistivity, potential, pH, redox, moisture, sulfates, life prediction, statistical treatment
Paper ID: STP39185S