AASHTO M 245
Standard Specification for Corrugated Steel Pipe, Polymer- Precoated, for Sewers and Drains
|Publication Date:||1 January 2020|
This specification covers polymer-precoated corrugated steel pipe intended for use for storm water drainage, underdrains, the construction of culverts, and similar uses. Pipe covered by this specification is not normally used for the conveyance of sanitary or industrial wastes. The steel sheet used in fabrication of the pipe has a polymer protective coating over a metallic coating of zinc (galvanizing), 55 percent aluminum-zinc alloy (55 Al-Zn), or zinc-5 percent aluminum- mischmetal alloy (Zn-5 Al-MM).
The polymer precoating provides a degree of extra protection for the pipe against abrasion and corrosion as compared with metallic-coated pipe without polymer coating. Some severe environments may cause corrosion problems to accessory items such as rivets or coupling band hardware that does not have a polymer coating. Additional protection for polymer-precoated corrugated steel pipe can be provided by use of coatings applied after fabrication of the pipe as described in M 190 and ASTM A849.
This specification does not include requirements for bedding, backfill, or the relationship between earth cover load and sheet thickness of the pipe. Experience has shown that the successful performance of this product depends on the proper selection of sheet thickness, type of bedding and backfill, controlled manufacture in the plant, and care in the installation. The installation procedure is described in the AASHTO LRFD Bridge Construction Specifications, Section 26.