1、Standard Practice for Evaluation of Protective Coating Systems for Structural Steel AASHTO Designation: R 31-09 (2014) American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS-4c R 31-1 AASHTO Standard Practice for Evaluati
2、on of Protective Coating Systems for Structural Steel AASHTO Designation: R 31-09 (2014) 1. SCOPE 1.1. This standard practice covers testing criteria for evaluation of protective coating systems for use on iron and steel surfaces. It is not recommended for the evaluation of hot-dip galvanizing or me
3、talizing. 1.2. The protective coating systems are intended for use on bridges, similar structural steel, and other ferrous metal surfaces, both new and existing, prepared by abrasive blast cleaning, which are subject to corrosive atmospheric environments, such as marine, industrial, deicing chemical
4、s, and high humidity. 1.3. The values stated in SI units are to be regarded as the standard. 1.4. This standard practice may involve hazardous materials, operations, and equipment. It does not purport to address all safety problems associated with its use. It is the responsibility of the user of thi
5、s standard practice to establish the appropriate safety and health practices and determine the applicability of regulatory limitations prior to use. Note 1The testing format for this standard practice has been developed around a three-coat system consisting of a zinc primer, epoxy or urethane interm
6、ediate, and an aliphatic urethane finish coat. 2. REFERENCED DOCUMENTS 2.1. Reference to standard specifications, testing procedures, and other standard procedures contained in this document shall be the latest edition of the published document at the date of this specification. 2.1.1. AASHTO Standa
7、rds: M 300, Inorganic Zinc-Rich Primer T 337, Non-Instrumental Determination of Metallic Zinc in Zinc-Rich Primers T 338, Analysis of Structural Steel Coatings for Hindered Amine Light Stabilizer (HALS) T 339, Analysis of Structural Steel Coatings for Isocyanate Content Standard Specifications for H
8、ighway Bridges 2.1.2. ASTM Standards: A36/A36M, Standard Specification for Carbon Structural Steel A325, Standard Specification for Structural Bolts, Steel, Heat Treated, 120/105 ksi Minimum Tensile Strength A490, Standard Specification for Structural Bolts, Alloy Steel, Heat Treated, 150 ksi Minimu
9、m Tensile Strength 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4c R 31-2 AASHTO A572/A 572M, Standard Specification for High-Strength Low-Alloy Columbium-Vanadium Structural Steel B117, Standard P
10、ractice for Operating Salt Spray (Fog) Apparatus D476, Standard Classification for Dry Pigmentary Titanium Dioxide Products D512, Standard Test Methods for Chloride Ion In Water D520, Standard Specification for Zinc Dust Pigment D521, Standard Test Methods for Chemical Analysis of Zinc Dust (Metalli
11、c Zinc Powder) D523, Standard Test Method for Specular Gloss D562, Standard Test Method for Consistency of Paints Measuring Krebs Unit (KU) Viscosity Using a Stormer-Type Viscometer D610, Standard Practice for Evaluating Degree of Rusting on Painted Steel Surfaces D714, Standard Test Method for Eval
12、uating Degree of Blistering of Paints D1475, Standard Test Method For Density of Liquid Coatings, Inks, and Related Products D1640/D1640M, Standard Test Methods for Drying, Curing, or Film Formation of Organic Coatings D1652, Standard Test Method for Epoxy Content of Epoxy Resins D1654, Standard Tes
13、t Method for Evaluation of Painted or Coated Specimens Subjected to Corrosive Environments D2073, Standard Test Methods for Total, Primary, Secondary, and Tertiary Amine Values of Fatty Amines, Amidoamines, and Diamines by Referee Potentiometric Method (Withdrawn 2007) D2196, Standard Test Methods f
14、or Rheological Properties of Non-Newtonian Materials by Rotational (Brookfield type) Viscometer D2240, Standard Test Method for Rubber PropertyDurometer Hardness D2244, Standard Practice for Calculation of Color Tolerances and Color Differences from Instrumentally Measured Color Coordinates D2369, S
15、tandard Test Method for Volatile Content of Coatings D2371, Standard Test Method for Pigment Content of Solvent-Reducible Paints D2697, Standard Test Method for Volume Nonvolatile Matter in Clear or Pigmented Coatings D2698, Standard Test Method for Determination of the Pigment Content of Solvent-Re
16、ducible Paints by High-Speed Centrifuging D3335, Standard Test Method for Low Concentrations of Lead, Cadmium, and Cobalt in Paint by Atomic Absorption Spectroscopy D3718, Standard Test Method for Low Concentrations of Chromium in Paint by Atomic Absorption Spectroscopy D3723, Standard Test Method f
17、or Pigment Content of Water-Emulsion Paints by Low-Temperature Ashing D3960, Standard Practice for Determining Volatile Organic Compound (VOC) Content of Paints and Related Coatings D4017, Standard Test Method for Water in Paints and Paint Materials by Karl Fischer Method D4060, Standard Test Method
18、 for Abrasion Resistance of Organic Coatings by the Taber Abraser D4285, Standard Test Method for Indicating Oil or Water in Compressed Air D4400, Standard Test Method for Sag Resistance of Paints Using a Multinotch Applicator D4417, Standard Test Methods for Field Measurement of Surface Profile of
19、Blast Cleaned Steel D4541, Standard Test Method for Pull-Off Strength of Coatings Using Portable Adhesion Testers 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4c R 31-3 AASHTO D4940, Standard Test
20、Method for Conductimetric Analysis of Water Soluble Ionic Contamination of Blasting Abrasives D5894, Standard Practice for Cyclic Salt Fog/UV Exposure of Painted Metal, (Alternating Exposures in a Fog/Dry Cabinet and a UV/Condensation Cabinet) D6133, Standard Test Method for Acetone, p-Chlorobenzotr
21、ifluoride, Methyl Acetate or t-Butyl Acetate Content of Solventborne and Waterborne Paints, Coatings, Resins, and Raw Materials by Direct Injection Into a Gas Chromatograph D6580, Standard Test Method for the Determination of Metallic Zinc Content in Both Zinc Dust Pigment and in Cured Films of Zinc
22、-Rich Coatings D7091, Standard Practice for Nondestructive Measurement of Dry Film Thickness of Nonmagnetic Coatings Applied to Ferrous Metals and Nonmagnetic, Nonconductive Coatings Applied to Non-Ferrous Metals E11, Standard Specification for Woven Wire Test Sieve Cloth and Test Sieves E1349, Stan
23、dard Test Method for Reflectance Factor and Color by Spectrophotometry Using Bidirectional (45:0 or 0:45) Geometry G92, Standard Practice for Characterization of Atmospheric Test Sites G140, Standard Test Method for Determining Atmospheric Chloride Deposition Rate by Wet Candle Method 2.1.3. Federal
24、 Standards:1 Fed. Std. No. 40, CFR 51.100(s), Volatile Organic Compound Definition Fed. Std. No. 40, CFR 59.406(a), Volatile Organic Compound Compliance Provision Fed. Std. No. 40, CFR Part 59, Subpart D, Section 59.400 Through 59.413, National Volatile Organic Compound Emission Standards for Archit
25、ectural Coatings Fed. Std. No. 40, CFR 261.24, Table 1, Maximum Concentration of Contaminants for the Toxicity Characteristic Fed. Std. No. 595, Colors Used in Government Procurement EPA SW 846, Method 1311, Toxicity Characteristic Leaching Procedure (TCLP) 2.1.4. ANSI Standard: American National St
26、andards Institute (ANSI) B94.50, Style E 2.1.5. The Society for Protective Coatings (SSPC) Standards:2 AB 2, Abrasive Specification No. 2, Cleanliness of Recycled Ferrous Metallic Abrasives AB 3, Abrasive Specification No. 3, Newly Manufactured or Re-Manufactured Steel Abrasive Guide 9, Guide for At
27、mospheric Testing of Coatings in the Field PA 2, Measurement of Dry Paint Thickness with Magnetic Gauges Paint 20, Zinc-Rich Primers SP 5, White Metal Blast Cleaning SP 6, Commercial Blast Cleaning SP 10, Near-White Blast Cleaning 2.1.6. Other Documents: Commercial Item Description (CID) A-A-1689B;
28、Tape, Pressure Sensitive Adhesive, Plastic Film3 Commission Internationale de lEclairage (CIE) 1976 L*a*b* “Appendix A, Testing Method to Determine the Slip Coefficient for Coatings Used in Bolted Joints,” Specification for Structural Joints Using ASTM A 325 or A 490 Bolts, as approved by the Resear
29、ch Council on Structural Connections4 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4c R 31-4 AASHTO 3. TERMINOLOGY 3.1. Definitions: 3.1.1. volatile organic compound (VOC)any organic compound that
30、participates in atmospheric photochemical reactions; that is, any organic compound other than those that the U.S. EPA Administrator designates as having negligible photochemical reactivity. For a list of compounds that the U.S. EPA Administrator has designated as having negligible photochemical reac
31、tivity, also referred to as “exempt compounds,” refer to 40 CFR 51.100(s). 3.1.2. VOC contentthe weight of VOC per volume of coating, calculated according to the procedures in 40 CFR 59.406(a). 3.1.3. dry film paint thicknessthe depth of coating to the top of the surface profile peaks, measured in a
32、ccordance with SSPC-PA 2. 3.1.4. minimum (laboratory) recoat timethe period of time required to sufficiently cure the applied coating when applied within the manufacturers recommended wet film thickness range and to obtain dry film thickness readings of the coating (without causing physical damage t
33、o the applied film). 4. CLASSIFICATION 4.1. PrimerPrimers act as the initial barrier over the prepared steel substrate. Single-coat systems shall consist only of the primer. Primers recommended for use on structures with painted connections designed for Class B allowable stress will be evaluated for
34、 Class B slip coefficient as detailed in Section 9.1 of this standard practice. Primers intended only for use on structures as maintenance applications (i.e., blast and recoat) may not be evaluated for Class B slip coefficient as detailed in Section 9.1 of this standard practice. 4.2. Touch-Up Prime
35、rThe touch-up primer shall be as recommended by the manufacturer at the time of application. Touch-up procedures for the intermediate and finish coats shall be detailed in the product data sheets or by written submission. 4.3. Intermediate CoatThe intermediate coat for a three-coat system serves as
36、a tie coat between primer and finish coat as well as a protective barrier for the structural steel. The manufacturers for each (three-coat) coating system submitted for evaluation shall recommend the appropriate intermediate coat. 4.4. Finish CoatThe finish coat for each system evaluated serves as t
37、he final barrier coating and provides the desired aesthetic finish for the surface of the structure. The manufacturers for each coating system submitted for evaluation shall recommend the appropriate finish coat. 5. MATERIALS 5.1. The materials used in the manufacture of the system shall conform to
38、the requirements of the following specifications: 5.1.1. Zinc DustASTM D520, Type II. 5.1.1.1. Manufacturers shall submit a certificate of analysis from the zinc suppliers showing conformance with the requirements. 2015 by the American Association of State Highway and Transportation Officials.All ri
39、ghts reserved. Duplication is a violation of applicable law.TS-4c R 31-5 AASHTO 5.1.1.2. Each coating (primer, intermediate, and finish coat) shall be tested by an NLLAP (National Lead Laboratory Accreditation Program) accredited laboratory to determine its total lead content. The total lead content
40、 shall be determined using a dry film sample in accordance with ASTM D3335. The percentage of total lead in each coating shall not exceed 0.01 percent (100 ppm). 6. GENERAL REQUIREMENTS 6.1. ColorFor production, the color of the coatings shall be as mutually agreed, except that the intermediate coat
41、 shall contrast in color a minimum of 10.0 E* from the primer to the finish coat. For testing purposes, the finish coat color shall comply to Section 8.2.7. 6.2. PigmentPrime pigments shall be used except for shaders. Leachable, heavy-metal compounds shall not exceed the regulatory limits of 40 CFR,
42、 261.24, Table 1, when tested in accordance with Section 9.7.4. Total levels of lead, cadmium, and chromium shall not exceed 20 times the specified limits for these elements. If titanium dioxide is used in the finish coat, it shall meet the requirements of ASTM D476, Type IV. 6.3. Slip Coefficient f
43、or PrimerPrimer coatings for use on new and rehabilitated structures with painted connections designed for Class B allowable stress shall meet the Class B slip coefficient requirements specified in the AASHTO Standard Specifications for Highway Bridges. The test data indicating compliance shall also
44、 state the type and quantity of reducer, cure time, and maximum coating thickness for that coating, as tested. 7. MANUFACTURERS REQUIREMENTS 7.1. The manufacturer shall supply chemical test results that will define the character and nature of the coating system being submitted. Actual results shall
45、be verified by the select laboratory, and shall be part of the select laboratorys report. Properties (determined in a mixed condition) shall be stated on the informational spreadsheet, certified Product Data Sheet, and/or the Material Safety Data Sheet as follows: 7.1.1. Total solids, percent by mas
46、s in accordance with ASTM D2369. 7.1.2. Volatile organic compound content in accordance with ASTM D3960. 7.1.3. EPA exempt solvents, identify compound and percent by volume. 7.1.4. Water, percent by mass, in accordance with ASTM D4017. 7.1.5. Pigment, percent by mass, in accordance with ASTM D2371 o
47、r D3723. 7.1.6. Metallic zinc content, percent by mass, in the primer shall be determined in accordance with ASTM D6580. An optional test method is T 337. 7.1.7. Total solids, percent by volume, in accordance with ASTM D2697. 7.1.8. Mass per volume (grams per liter) in accordance with ASTM D1475. 7.
48、1.9. Viscosity (Stormer at 25C) KU in accordance with ASTM D562 (not suitable for viscosities above 143 KU). 7.1.10. Viscosity (Brookfield at 25C) cP in accordance with ASTM D2196. The instrument model (i.e., LV, DV, DVII+), spindle size, and revolutions per minute shall be reported. 2015 by the Ame
49、rican Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4c R 31-6 AASHTO 7.1.11. Pot life in hours, at specified temperature and specified humidity, shall be evaluated in the laboratory through viscosity measurements taken at regular intervals and reported in Krebs units. Materials with manufacturers stated pot life shall be evaluated at 25, 50, 75, and 1
