444 SECTION 852
852.01 Paints and Enamels
A.Lamp Black Use lamp black pigment that meets ASTM D 209.
B.Chrome Yellow and Chrome Orange Use chrome yellow and chrome orange pigments that meet ASTM D 211.
C.Enamels. Use enamel that meets the general requirements of Federal Specifications A -A-2962A, Notice 2 Enamel, Alkyd, Exterior, Solvent Based, Low VOCm with the following exceptions:
1.Alkyd resin shall be a Type I or Type II alkyd meeting Federal Specification TT-R -266 Resin, Alkyd; Solutions.
2.Specular gloss, 60 degrees, shall be in the range of 40 to 70.
852.02 Three Coat Organic Zinc Rich Paint System
A.Materials.
1.General. Use a three- coat paint system consisting of an organic zinc -rich epoxy primer, a polyamide epoxy intermediate coat, and an aliphatic polyurethane finish coat. Submit the three-coat system to the NTPEP testing program and submit the results to the Department. Provide a system from a single manufacturer. Provide components that are recommended for use as part of a three-coat system.
2.Organic Zin c-Rich Epoxy Primer. Use an organic zinc -rich epoxy primer that is a multi -component, solvent based, chemically -curing, polyamide epoxy system. Use zinc dust pigment meeting the requirements of ASTM D 520, Type II. Use primer capable of being spray applied to the manufacturer's recommended Dry Film Thickness (DFT) in one coat without sagging or mud cracking. After mixing the primer shall be smooth and uniform, and free of lumps or coarse particles. Formulate the color of the primer to produce a distinct contrast with the blast cleaned steel and the subsequent intermediate coat. Add tinting materials that are inert and do not reduce the effectiveness of the galvanic protection.
3.Intermediate Coat. Use a two component chemically -curing polyamide epoxy for the intermediate coat. Mix the paint to be smooth, uniform, and capable of being spray applied. Formulate the color of the intermediate coat to produce a distinct contrast with the primer and the finish coat. 445 4. Finish Coat. Use a compatible two-component, aliphatic polyurethane finish coat with a weather resistant finish and the gloss and color as specified in the plans.
B.Certification and Acceptance.
1.General. Submit a certification for the paint system that is less than 5 years old. The certification must be from the NTPEP Structural Steel Coatings Testing Program and the testing must meet the requirements of AASHTO R 31 and this specification. In addition to the requirements of Section 106.01 C, “Certificate of Compliance” , submit the following information: − Manufacturer Contact Information; − Completed NTPEP Test Data; − Product Data Sheets; and − Material Safety Data Sheets.
2.Slip Coefficient. Report results only.
3.Salt Fog Resistance. Use an exposure duration of 5,000 hours.
a.Blistering. Use a coating that has a blistering conversion value of 7 or better.
b.Rust Creep. Use a coating that shows no rust creep larger than 8 mm and that has a maximum average creep of 4 mm. Use a coating that shows no signs of rust outside the cutback.
4.Cyclic Weathering Resistance Test. Use an exposure duration of 5,000 hours.
a.Blistering. Use a coating that has a blistering conversion value of 7 or better.
b.Rust Creep. Use a coating that shows no rust creep larger than 8 mm and that has a maximum average creep of 4 mm. Use a coating that shows no signs of rust outside the cutback.
5.Abrasion Resistance. Report results only.
6.Adhesion. Use a coating system that has an adhesion of 600 psi.
7.Freeze Thaw Stability. Use a full system with a minimum adhesion of no less than 60% of the adhesion value recorded in Section 852.02 B.6, “Adhesion” .
8.Coating Identification Tests. Volatile organic content for each component of the system shall be a maximum of 3.5 pounds per gallon.
a.Organic Zinc-Rich Epoxy Primer. Provide primer with a minimum of 70 percent total solids, by weight. Provide primer with a minimum of 75 percent zinc pigment, by weight of total solids.
b.Intermediate Coat. Provide an intermediate coat with a minimum of 54 percent total solids, by weight.
c.Finish Coat. Provide a finish coat with a minimum of 54 percent total solids, by weight.
C.Packaging and Labeling Provide a label on each container that contains: - The name of the manufacturer; - The brand name; - The lot number of the paint; - Complete instructions for the use of the paint; - The shelf life of the c omponents; and - The pot life of the mixture. Section 854 447 SECTION 854 GALVANIZING
854.01 Galvanizing
Galvanize iron and steel products to meet AASHTO M 111. Galvanize Iron and Steel Hardware to meet AASHTO M 232.
854.02 Damaged Galvanized Coatings
Repair damaged galvanized coatings to meet ASTM A 780.
Source: North Dakota Standard Specifications for Road and Bridge Construction, 2022 Edition. Pages 479–481 of 550.