This paper was presented at the `Strategic investments in structures' session. While galvanized Corrugated Steel Pipe (CSP) performs well in many environments, there are some aggressive sites where it can be subject to premature corrosion. There are add-on coatings and pavings available which can extend the service life of galvanized (zinc coated) CSP. There is also an alternative to galvanized CSP in the form of a more corrosion resistant product manufactured using Aluminized Steel Type 2. This paper presents a review of corrosion as it relates to CSP. The different corrosion mechanisms affecting zinc coated and aluminum coated CSP are discussed and compared. The paper discusses the various types of protection mechanisms provided by metallic coatings. Field testing methodology and the results of the field studies are presented and interpreted. Approaches to service life prediction are reviewed and discussed. (A)
Abstract