Proposed AASHTO M 180 Specification Update W/ Redline Strikeout

and detection of inadequate tensile strength, yield strength, elongation, improper coating, deficient thickness, or improper fabrication, the material will be rejected and approval for further use withdrawn until subsequently reapproved. Samples for test of any material offered for use may be taken at any time deemed desirable by the engineer. 5.3.2. The manufacturer or fabricator shall make such tests and measurements as necessary to ensure that the material produced complies with all specification requirements. These tests and measurements shall be so identified by the identification symbols or code used on the beamsheet steel components, steel guardrail posts or anchor wire rope and swage fittings that the manufacturer can produce specific reports showing these test results. Copies of reports of these tests shall be kept on file and shall be submitted to the engineer on request. 5.3.3. The brand shall be removed or obliterated by the manufacturer or fabricator on all material where control tests, as outlined herein, do not show conformance to this specification. MATERIALS 6.1. Base Metal for Sheet Steel—The guardrail beams, transition beams, end sections, buffer sections, terminal connectors, and backup plates shall consist of sheet produced from electric arc furnace or basic oxygen furnace steel and shall meet the mechanical properties specified in Section 8. The chemical composition of the base metal for Type IV beams shall be as approved by the engineer. 6.1.1. All sheet steel components including guardrail beams, transition beams, end sections, buffer sections, terminal connectors, and backup plates shall be the same Type (i.e., coating) as the guardrail beam to which it is attached. 6.1.2. End Section or Buffer Section – The material for eEnd sections or and buffer sections material shall be of the same or greater metal thickness (i.e., Class) of the metal and the same type as the guardrail beam beam to which it is attached, unless otherwise specified by or the engineer may specify the minimum thickness of the metal and type. Backup Plates—Backup plates if specified for use at non-splice points shall consist of 305-mm (1ft) sections of beams and shall be of the same class and type specified for the full-length beams. 6.1.6.2. Zinc—The zinc used for the coating of Types I and II sections shall be as prescribed in ASTM B6, and shall be at least equal to the grade designated as “Prime Western.” 6.3. Zinc-Aluminum-Magnesium Alloy—The zinc-aluminum-magnesium alloy for Types V and VI shall contain 5–13 percent aluminum, 2–4 percent magnesium, and up to 1 percent total additional alloying elements (except iron), and the balance shall be zinc as prescribed in ASTM A1046/A1046M Section 6.2 Coating Bath Composition, Table 6 Type 1. 6.4. Fasteners: 6.1.1. Bolts and Nuts: 6.4.1. Standard Strength Bolts: 6.1.1.1.6.4.1.1. Unless otherwise specified, standard strength bolts and nuts for used with Types I, II, and III, V, and VI beams sheet steel components or steel guardrail posts shall conform to or exceed the requirements of ASTM A307 Grade A (ASTM F568M Class 4.6) and shall be coated in accordance with Section 9.49.2.2 of this specification. TS-4d M 180-6 AASHTO

6.1.1.2.6.4.1.2. Standard strength Bbolts and nuts for used with Type IV beams sheet steel components or steel guardrail posts shall be of an approved atmospheric corrosion -resistant material and conform to or exceed the requirements of ASTM A307 Grade A. 6.4.1.3. Thread profiles shall conform to ANSI/ASME B1.1 for 5/8-11 UNC (ASME B1.13 for M16x2) for Class 2A (6g) tolerances. 6.4.1.4. All beam-to-post connections or beam-to-beam splices shall be formed with oval shoulder, buttonheaded bolts to minimize projections on the roadside traffic side of the guardrail. Standard strength bolts used in sSplice and post connectionsbolts and nuts shall conform to one of the configurations shown in Figures 1 or 2 Figure 1. Either of the alternate configurations may be furnished unless otherwise specified by the engineer. 6.4.2. High-Strength Bolts: 6.4.2.1. Unless otherwise specified, high-strength bolts used with Types I, II, III, V, and VI sheet steel components shall conform to or exceed the requirements of ASTM F3125/F3125M Grade A325 Type 1 and shall be coated in accordance with Section 9.2.3 of this specification. 6.4.2.2. High-strength bolts used with Type IV sheet steel components shall be of an approved atmospheric corrosion resistant material and conform to or exceed the requirements of ASTM F3125/F3125M Grade A325 Type 3. 6.4.3. Nuts: 6.4.3.1. Unless otherwise specified, nuts used with Types I, II, III, V, and VI sheet steel components or steel guardrail posts shall conform to or exceed the requirements of ASTM A563 Grade A Heavy Hex (ASTM A563M Class 5 (overtapped)) and shall be coated in accordance with Section 9.2.4 of this specification. 6.4.3.2. Nuts used with Type IV sheet steel components or steel guardrail posts shall be of an approved atmospheric corrosion resistant material and conform to or exceed the requirements of ASTM A563 Grade C3 Heavy Hex (ASTM A563M Class 8S3). 6.4.3.3. Nuts used in splice and post connections shall conform to the configuration shown in Figure 1. The nut may have recesses on one or both sides. 6.4.4. Washers: 6.4.4.1. Plain round washers, when specified under a nut, shall be manufactured according to the requirements of ASME B18.21.1 Type B (ASME B18.22M Type B). When required, the washers shall be galvanized in accordance with Section 9.2.5 of this specification. 6.4.4.2. Hardened washers used with high-strength fasteners shall be manufactured according to the requirements of ASTM F436/F436M Type 1 and coated in accordance with Section 9.2.5 of this specification unless atmospheric corrosion resistant steel washers are used. When atmospheric corrosion resistant steel washers are used, they shall be manufactured according to the requirements of ASTM F436/F436M Type 3. 6.4.4.3. Washers, when specified under the head of button-head shouldered bolts, shall be rectangular with a slotted hole, as shown in Figure 3Figure 2. Washers are not to be used under the bolt-head for strong-post guardrails unless specified by the designer. 6.4.4.4. Washers, when specified under the head of hex-head bolts, such as used in some weak-post systems, shall be square with a round hole, as shown in Figure 2. TS-4d M 180-7 AASHTO

6.1.1.3.6.4.4.5. Rectangular or square Wwashers used with Types I, II, III, V, and VI beams sheet steel components or steel guardrail posts shall be manufactured from ASTM A653/A653M SS Grade 37 or equivalent steel and shall be galvanized in accordance with Section 9.2.6 of this specification. Unless otherwise specified, Wwashers used with for Type IV beams sheet steel components shall be manufactured from ASTM A606/A606M or other of an approved atmospheric corrosion- resistant steel. 6.5. Steel Guardrail Posts: 6.5.1. Steel guardrail posts shall meet the mechanical properties specified in Section 8 and coating requirements specified in Section 9 of this specification. Acceptable materials and grades include but are not limited to the following standards: M 270M/M 270, Grade 36 (250) or Grade 50S (345S) with the exception of supplementary requirements, ASTM A36/A36M, ASTM A572/A572M Grade 42 or Grade 50, or ASTM A992/A992M. 6.5.2. Where atmospheric corrosion resistant steel is required, the steel guardrail posts shall meet the mechanical properties specified in Section 8. Acceptable materials and grades include but are not limited to the following standards: M 270M/M 270, Grade 50W (345W) (equivalent to ASTM A709/A709M 50W), or ASTM A588/A588M. 6.6. Anchorage Wire Rope and Swage Fittings: 6.6.1. The anchor wire rope shall be 0.75 in. (19 mm) diameter, Metallic-Coated Wire Rope, Type II(a) 6x19 wire-strand core or Type II independent wire rope core (IWRC), right regular lay wire rope. 6.6.2. The anchor wire rope swage fittings shall be machined from hot-rolled carbon steel conforming to ASTM A576 Grade 1035. The material shall be suitably annealed for cold swaging. 6.6.3. A lock pin hole shall be drilled through the head off the anchor wire rope swage fitting and a 0.25 in. (6 mm) plated spring-steel pin shall be installed into the hole to retain the stud in the proper position. 6.6.4. Materials used for anchorage wire rope and swage fittings (typically used as part of a trailing end anchor) under this specification shall follow the requirements of M 30 Section 5 Material. 6.2. End or Buffer Sections: 6.2.1. End or buffer sections shall be of the same or greater thickness of the metal and the same type as the beam to which it is attached, or the engineer may specify the minimum thickness of the metal and type. TS-4d M 180-8 AASHTO

MANUFACTURE 7.1. The Guardrail beams, transition beams, and end sections, or buffer sections, and terminal connectors shall be shaped and punched in conformance with the requirements shown in Figures 3 2 and 43. Transition beams sections shall be fabricated in accordance with Figure 5 4 and shall provide a smooth and uniform transition between guardrail beams. Two common methods for shaping sheet steel components are roll forming and press forming; these two processes result in different levels of springback which must be accounted for in the forming process to ensure proper bolt hole alignment, nesting and lapping of sheet steel components. They Sheet steel components shall be ready for assembly when delivered. 7.1.7.2. Only drilling or cutting necessary for special connections and for sampling will be permitted in the field. Warped or deformed beams will be rejected. Guardrail Bbeams to be erected on a radius of 46 m (150 ft)150 ft (46 m) or less shall be shop-curved to the appropriate curvature of the installation. Shop-curved guardrail beam shall be provided in 5-ft (1.5 m) increments of curvature with a minimum radius of curvature of 5 ft (1.5 m). Due to the nature of long lengths of guardrail beam there is flexibility to match the curvature required upon installation in the field. MECHANICAL PROPERTIES 8.1. The mechanical properties of the base metal for sheet steel components shall conform to the following requirements: 8.1.1. Guardrail Beams,s and Transition Beams Sections, and Terminal Connectors: Yield point, minimum, 345 MPa (50,000 psi)50 ksi (345 MPa); Tensile strength, minimum 483 MPa (70,000 psi)70 ksi (483 MPa); and Elongation, in 50 mm (2 in.)2 in. (50 mm), minimum, 12 16 percent. 8.1.2. End Sections, and Buffer Sections, and Backup Plates: Yield point, minimum, 227 MPa (33,000 psi)33 ksi (227 MPa); and Tensile strength, minimum 310 MPa (45,000 psi) 45 ksi (310 MPa). 8.1.3. Test specimens for mechanical properties testing shall be prepared and tested as specified in ASTM A924/A924M. Correction for thickness of specimens shall be as follows: Table 1—Weight of Coating and Thickness CorrectionRequirements Weight of Coating (Total Both Sides) Minimum Single-Spot Minimum Triple-Spot Type I II V VI a b Minimum Single-Spot Correction Side Coating Thicknessa, oz/ft2 g/m2 oz/ft2 g/m2 in.mils mmµm 1.80 3.60 0.80 1.00 550 1100 245 305 2.00 4.00 0.90 1.15 610 1220 275 350 0.00301.5b 0.00603.0b 0.00160.8c 0.00201.0c 0.0838.5b 0.1577.0b 0.0420.4c 0.0525.4c galvanized coating mass : thickness zinc-aluminum-magnesium alloy coating mass : thickness 1.00 oz/ft2 1.68 mils (7.14 g/m2 1.00 μm) (1.00 oz/ft2 1.68 mils) 1.00 oz/ft2 2.00 mils (6.01 g/m2 1.00 μm) (1.00 oz/ft2 2.00 mils) 8.2. The mechanical properties of the guardrail fasteners shall conform to the following requirements: 8.2.1. Standard Strength Bolts: Shall conform to the mechanical property requirements specified in the appropriate referenced standards identified in the Subsections of 6.4.1 of this specification. 8.2.2. High-Strength Bolts: TS-4d M 180-9 AASHTO

Shall conform to the mechanical property requirements specified in the appropriate referenced standards identified in the Subsections of 6.4.2 of this specification. 8.2.3. Nuts: Shall conform to the proof load requirements specified in the appropriate referenced standards identified in the Subsections of 6.4.3 of this specification. 8.2.4. Washers: Shall conform to the mechanical property requirements specified in the appropriate referenced standards identified in the Subsections of 6.4.4 of this specification. 8.3. The mechanical properties of the steel guardrail posts shall conform to the appropriate referenced standards identified in Subsections of 6.5 of this specification and the following requirements, unless otherwise specified by the engineer: Yield point, minimum, 36 ksi (250 MPa); Tensile strength, 58 – 80 ksi (400 – 550 MPa); and Elongation, in 2 in. (50 mm), minimum, 21 percent. 8.4. The mechanical properties of anchor wire rope and swage fittings shall conform to the following requirements: 8.4.1. Anchorage Wire Rope: The anchor wire rope steel shall be improved steel with a minimum breaking strength of 42.8 kips (190 kN). 8.4.2. Anchorage Wire Rope Swage Fittings: The anchor wire rope swage fitting, stud, and nut shall develop the full breaking strength of the wire rope. COATING REQUIREMENTS 9.1. Sheet Steel Components: Table 1—Coating Weight and Thickness Requirements Coating Weight (Total Both Sides) Minimum Single-Spot Minimum Triple-Spot Type I II V VI a b c d Minimum Single-Spot Single Side Coating Thicknessa oz/ft2 g/m2 oz/ft2 g/m2 mils µm 1.80 3.60 0.80 1.00 550 1100 245 305 2.00 4.00 0.90 1.15 610 1220 275 350 1.5b 3.0b 0.8c 1.0c 38.5b 77.0b 20.4c 25.4c values in these columns correspond to the thickness value converted from the minimum single-spot column divided by 2 which results in a single sided thickness value galvanized coating thickness conversion: 1.00 oz/ft2 1.68 mils (7.14 g/m2 1.00 μm) zinc-aluminum-magnesium alloy coating thickness conversion: 1.00 oz/ft2 2.00 mils (6.01 g/m2 1.00 μm) The “Spot” shall be a randomly selected location on the finished sheet steel component. The “Weight” in Table 1 is deemed to be the combined coating weight on both sides of the sheet steel component at that spot. 9.1.1. Type I and II Beams: 9.1.2. Type I and II Sheet Steel Components—The beams sheet steel components may be galvanized before or after fabrication. Beams Sheet steel components galvanized before fabrication shall be coated in accordance with ASTM A653/A653M. Beams Sheet steel components galvanized after fabrication shall conform to the requirements of M 111M/M 111, excluding the one grade less TS-4d M 180-10 AASHTO

clause of M 111M/M 111 Section 6.1. Coating and testing requirements listed under M 180these specifications shall govern. Sampling and testing not listed under M 180these specifications shall be conducted in accordance with the referenced coating specification. 9.1.2.1.9.1.1.1. The mass of coating shall conform to the requirements prescribed in Table 2Table 1 for the types specified. The mass of coating is the total amount of galvanizing on both sides of a sheet or beamsteel component, expressed as grams per square meter (ounces per square foot)ounces per square foot (grams per square meter) of the sheet or beamsteel component. Table 2—Weight of Coating Min Check Limit Single-Spot Test Type I II Weight of Coating Min Check Limit Triple-Spot Test g/m2 oz/ft2 g/m2 oz/ft2 550 1100 1.80 3.60 610 1220 2.00 4.00 Note: The “Spot” in Spot Test shall be a randomly selected location on the finished beam or sheet. The “Weight” of coating in Table 2 is deemed to be the combined weight on both sides of the beam or sheet at that spot. 9.1.2.2.9.1.1.2. The sheets or beams zinc coating shall be of prime finish, that is, free from injurious defects such as blisters, flux, and uncoated spots. Uncoated edges resulting from transverse shearing or punching of holes will not be considered objectionable. 9.1.2.3.9.1.1.3. The coating shall be smooth, free of beading or sharp projections along the edges, and shall adhere tenaciously to the surface of the metal. The adherence of the zinc coating to the surface of the base metal shall be determined by cutting or prying with a stout knife, applied with considerable pressure in a manner tending to remove a portion of the coating by paring or whittling, and it shall not be possible to peel any portion of the coating so as to expose the base metal. 9.1.2.4.9.1.1.4. Precautions shall be taken during the shipping and storage processes to limit the opportunity for wet storage stain (i.e., white rust) to form before the protective patina is formed on the galvanized surface. Sheet steel components shall be arranged to encourage airflow and limit standing water on the galvanized surface, along with water repellent or barrier coatings to eliminate the formation of wet storage stain. If areas affected by wet storage stain become darker or show signs of red rust the area shall be cleaned, the remaining coating thickness checked, and if required touch-up galvanizing shall be performed as prescribed in Section 9.5 of this specification. 9.1.1.5. The test specimen size and method of tests for determining the mass of coating shall be as prescribed in T 65M/T 65. At the option of the engineer, material sheet steel components may be accepted on the basis of magnetic gauge determinations made in accordance with ASTM E376 and conforming to the values in Table 1. 9.1.3. Type III Beams: 9.1.4.9.1.2. Type III Sheet Steel Components—Beams Sheet steel components that are to be painted shall be cleaned and shop-painted with one coat of rust-inhibitive primer. The primer shall have a tough and durable surface and shall be thoroughly dry before the sheets steel components are handled or packed for shipment. 9.2. Type IV Beams: TS-4d M 180-11 AASHTO

9.1.3. Type IV Sheet Steel Components—Beams Sheet steel components made of atmospheric corrosion -resistant steel shall not be painted or galvanized. They shall be so handled and stored so that the traffic face of these beamssheet steel components, used in a continuous run of guardrail, shall not show a distinctive color differential. Note 1— When Type IV sheet steel components are in direct contact with each other or wi

Proposed AASHTO M 180 Specification Update NCHRP 22-40 UPDATE TO AASHTO M 180-18 AND ASSOCIATED HIGHWAY GUARDRAIL SPECIFICATIONS Proposed AASHTO M 180 Specification Update w/ Redline Strikeout 6 July 2021 Chuck A. Plaxico, Ph.D. Ethan M. Ray Roadsafe LLC P. O. Box 312 12 Main Street Canton Maine 04221 TRANSPORTATION RESEARCH BOARD NAS-NRC