1、Standard Specification for Corrugated Sheet Steel Beams for Highway Guardrail AASHTO Designation: M 180-12 American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001TS-4d M 180-1 AASHTO Standard Specification for Corrugated Shee
2、t Steel Beams for Highway Guardrail AASHTO Designation: M 180-12 1. SCOPE 1.1. This specification covers corrugated sheet steel prepared for use as beams in highway guardrails. 1.2. The values stated in SI units are to be regarded as the standard. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standards: M 111
3、M/M 111, Zinc (Hot-Dip Galvanized) Coatings on Iron and Steel Products M 232M/M 232, Zinc Coating (Hot-Dip) on Iron and Steel Hardware T 65M/T 65, Mass Weight of Coating on Iron and Steel Articles with Zinc or Zinc-Alloy Coatings 2.2. ASTM Standards: A307, Standard Specification for Carbon Steel Bol
4、ts, Studs, and Threaded Rod 60 000 psi Tensile Strength A563M, Standard Specification for Carbon and Alloy Steel Nuts (Metric) A653/A653M, Standard Specification for Steel Sheet, Zinc-Coated (Galvanized), or Zinc-Iron Alloy-Coated (Galvannealed) by the Hot-Dip Process B6, Standard Specification for
5、Zinc B695, Standard Specification for Coatings of Zinc Mechanically Deposited on Iron and Steel E376, Standard Practice for Measuring Coating Thickness by Magnetic-Field or Eddy-Current (Electromagnetic) Testing Methods F568M, Standard Specification for Carbon and Alloy Steel Externally Threaded Met
6、ric Fasteners (withdrawn 2012) 2.3. ANSI Standards: B1.13M, Metric Screw Threads D M Profile B18.2.4.1M, Hex Nuts, Style 1, Metric B18.2.4.6M, Hex Nuts, Heavy, Metric 2.4. Federal Standard: TT-P-641, Type II Zinc Dust Primer for Steel or Galvanized Metal Surfaces 2.5. Military Standard: DOD-P-21035,
7、 Paint, High Zinc Dust Content, Galvanizing Repair (Metric) 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4d M 180-2 AASHTO 3. CLASSIFICATION 3.1. Four types and two classes of guardrail are provide
8、d as follows: 3.1.1. Types: Type IZinc-coated, 550 g/m2(1.80 oz/ft2) minimum single-spot. Type IIZinc-coated, 1100 g/m2(3.60 oz/ft2) minimum single-spot. Type IIIBeams to be painted. Type IVBeams of corrosion resistant steel. 3.1.2. Classes: Class ABase metal nominal thickness2.67 mm (0.105 in.). Cl
9、ass BBase metal nominal thickness3.43 mm (0.135 in.). 4. ORDERING INFORMATION 4.1. Orders for guardrail under this specification shall include the following information, as required, to adequately describe the desired material: 4.1.1. Quantity (linear meter or number of pieces), 4.1.2. Class of guar
10、drail, 4.1.3. Type of guardrail, 4.1.4. Effective length of beam section 3.8 or 7.6 m (12.5 ft or 25.0 ft), 4.1.5. Shape (W-beam or thrie beam), and 4.1.6. Exceptions to this specification or special requirements, if any. 5. BASIS OF ACCEPTANCE 5.1. All material shall be subject to inspection and sa
11、mpling at the fabricating plant, warehouse, or after delivery to the site of construction. 5.2. Acceptance by Sampling: 5.2.1. The engineer may take one piece of guardrail, a backup plate, and end or buffer section from each 200 pieces in a lot, or from each lot if less than 200 pieces are included
12、therein, for determination of compliance with specification requirements. If one piece fails to meet the requirements, two other pieces shall be tested. If either of these pieces fails to conform to the requirements of this specification, the lot of material represented by these samples shall be rej
13、ected. A lot shall be considered that quantity of material offered for inspection at one time that bears the same heat and coating identification. 5.3. Acceptance by Brand Registration and Guarantee: 5.3.1. By mutual agreement between the fabricator and engineer, acceptance may be based upon a brand
14、 registration and guarantee filed with the engineer by the fabricator. For acceptance of a brand, the fabricator shall furnish a brand registration and guarantee meeting the approval of the engineer and 2015 by the American Association of State Highway and Transportation Officials.All rights reserve
15、d. Duplication is a violation of applicable law.TS-4d M 180-3 AASHTO showing the brand name or designation, the manner in which it will appear on the fabricated beams, the typical mechanical properties, chemical composition if specified, the class and type of guardrail, and other specified propertie
16、s. The fabricator shall also guarantee that as long as material is furnished under that brand and designation, it will conform fully to the requirements of the specification and shall be replaced without cost to the engineer when found not in conformity with any of the specified requirements. The br
17、and registration and guarantee shall be sworn to for the fabricator by a person having legal authority to bind the company. Upon approval of a brand registration and guarantee, that brand will be accepted without further certification. If, in subsequent actual field use, there is evidence of misbran
18、ding as determined by random sampling 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
19、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 id
20、entified by the identification symbols or code used on the beam 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 upon request. 5.3.3. The brand shall be removed or obliterated
21、by the manufacturer or fabricator on all material where control tests, as outlined herein, do not show conformance to this specification. 6. MATERIALS 6.1. Base MetalThe beam, transition, end, and buffer sections shall consist of sheet made of open hearth, electric furnace, or basic oxygen steel and
22、 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. 6.2. ZincThe zinc used for the coating of Type I and II sections shall be as prescribed in ASTM B6, and shall be at least equal to the grad
23、e designated as “Prime Western.” 6.3. Bolts and Nuts: 6.3.1. Unless otherwise specified, bolts and nuts for Types I, II, and III beams shall conform to or exceed the requirements of ASTM A307 and shall be coated in accordance with Section 9.4. 6.3.2. Bolts and nuts for Type IV beams shall be of an a
24、pproved corrosion resistant material and conform to or exceed the requirements of ASTM A307. 6.3.3. All connections or splices shall be formed with oval shoulder button headed bolts to minimize projections on the roadside of the guardrail. Splice and post bolts and nuts shall conform to one of the c
25、onfigurations shown in Figures 1 or 2. Either of the alternate configurations may be furnished unless otherwise specified by the engineer. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4d M 180-4 AA
26、SHTO Note: Oval shoulder shall have smooth radii and shall maintain an essentially full vertical height of the apex of the oval. All dimensions shown on Alternate Bolt No. 1 also apply to Alternate Bolt No. 2. All dimensions are subject to manufacturers tolerances except where allowable tolerances a
27、re shown. Figure 115.88-mm (5/8-in.) Post or Splice Bolt and Nut 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4d M 180-5 AASHTO Notes: 1. The bolt shall have M16 2 threads as defined in ANSI B1.13M
28、 for Grade 6 g tolerances. Bolt material shall conform to ASTM F568M (withdrawn 2012) for Class 4.6. Material for corrosion resistant bolts shall conform to ASTM F568M for Class 8.8.3 bolts. 2. Nuts shall have ANSI B1.13M M16 2 Grade 6H threads. The geometry of the nuts, with the exception of the re
29、cess shown in the drawing, shall conform to ANSI B 18.2.4.1M Style 1 for zinc-coated hex nuts, and ANSI B18.2.4.6M heavy-hex corrosion-resistant nuts shall conform to the requirements of ASTM A563M for Class 8S3. Zinc-coated nuts shall be tapped oversize as specified in ASTM A563M, except that a dia
30、metrical allowance of 510 mm shall be used instead of 420 mm. 3. Dimensional tolerances not shown or implied are intended to be those consistent with the proper functioning of the part, including its appearance and accepted manufacturing practices. Figure 216-mm Post or Splice Metric Bolt and Nut 6.
31、4. Washers and Backup Plates: 6.4.1. Washers shall be rectangular as shown in Figure 3. Washers for Types I, II, and III beams shall be galvanized in accordance with Section 9. Washers for Type IV beams shall be of an approved corrosion-resistant steel. Backup plates if specified for use at non-spli
32、ce points shall consist of 305-mm (1-ft) sections of beams and shall be of the same class and type specified for the full-length beams. 6.5. End or Buffer Sections: 6.5.1. 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 attac
33、hed, or the engineer may specify the minimum thickness of the metal and type. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-4d M 180-6 AASHTO 7. MANUFACTURE 7.1. The beams and end or buffer sections
34、 shall be shaped and punched in conformance with the requirements shown in Figures 3 and 4. Transition sections shall be fabricated in accordance with Figure 5 and shall provide a smooth and uniform transition between beams. They shall be ready for assembly when delivered. Only drilling or cutting n
35、ecessary for special connections and for sampling will be permitted in the field. Warped or deformed beams will be rejected. Beams to be erected on a radius of 46 m (150 ft) or less shall be shop curved to the appropriate curvature of the installation. 8. MECHANICAL PROPERTIES 8.1. The mechanical pr
36、operties of the base metal shall conform to the following requirements: 8.1.1. Beams and Transition Sections: Yield point, minimum, 345 MPa (50,000 psi); Tensile strength, minimum 483 MPa (70,000 psi); and Elongation, in 50 mm (2 in.), minimum, 12 percent. 8.1.2. End and Buffer Sections: Yield point
37、, minimum, 227 MPa (33,000 psi); and Tensile strength, minimum 310 MPa (45,000 psi). 8.1.3. Test specimens for mechanical properties shall be prepared and tested as specified in ASTM A653/A653M except that correction for thickness of zinc-coated specimens shall be 0.08 mm (0.003 in.) for Type I beam
38、 and 0.15 mm (0.006 in.) for Type II beam. 9. COATING REQUIREMENTS 9.1. Type I and II Beams: 9.1.1. The beams may be galvanized before or after fabrication. Beams galvanized before fabrication shall be coated in accordance with ASTM A653/A653M. Beams galvanized after fabrication shall conform to the
39、 requirements of M 111M/M 111. Coating and testing requirements listed under M 180 shall govern. Sampling and testing not listed under M 180 shall be conducted in accordance with the referenced coating specification. 9.1.2. The mass of coating shall conform to the requirements prescribed in Table 1
40、for the types specified. The mass of coating is the total amount of galvanizing on both sides of a sheet or beam, expressed as grams per square meter (ounces per square foot) of the sheet or beam. Table 1Weight of Coating Weight of Coating Min Check Limit Single-Spot Test Min Check Limit Triple-Spot
41、 Test Type g/m2oz/ft2g/m2oz/ft2I 550 1.80 610 2.00 II 1100 3.60 1220 4.00 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.Notes: 1. All dimensions are subject to manufacturers tolerances except where all
42、owable tolerances are shown. 2. All dimensions shown in millimeters unless otherwise noted. (All parenthetical values are in inches unless otherwise noted.) 3. Rectangular plate washers are optional only in the transition sections. They are not to be used in the main sections of strong-post guardrai
43、l. Figure 3W-Beam TS-4dM 180-7AASHTO 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.Notes: 1. All dimensions are subject to manufacturers tolerances except where allowable tolerances are shown. 2. All d
44、imensions shown in millimeters unless otherwise noted. (All parenthetical values are in inches unless otherwise noted.) 3. Rectangular plate washers are optional only in the transition sections. They are not to be used in the main sections of strong-post guardrail. Figure 4Thrie Beam TS-4dM 180-8AAS
45、HTO 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.Figure 5Transition Section TS-4dM 180-9AASHTO 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Dupli
46、cation is a violation of applicable law.TS-4d M 180-10 AASHTO 9.1.3. The sheets or beams 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 objectiona
47、ble. 9.1.4. 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 consid
48、erable 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. 9.1.5. The test specimen size and method of tests for determining the mass of coating shall be as prescribed
49、in T 65M/T 65. At the option of the engineer, material may be accepted on the basis of magnetic gauge determinations made in accordance with ASTM E376. 9.2. Type III Beams: 9.2.1. Beams 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 are handled or packed for shipment. 9.3. Type IV Beams: 9.3.1. Beams of corrosion-resistant steel shall not be painted or galvanized. They
