American Railway Engineering & Maintenance-of-Way Association Letter Ballot No

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1 Letter Ballot No Assignment: At the May 2017 meeting in Buffalo, NY the Committee members present voted to submit the following for letter ballot: Move to Commentary tables that repeat ASTM A709 information in favor of direct reference to ASTM A709 and other ASTM specifications Rationale: The data in Tables , , and refer directly to the ASTM specifications for structural steel and have historically been provided in the Chapter as reference material Because the ASTM specifications are modified at intervals that do not coincide with AREMA Manual updates, there is a potential for the information provided in the Chapter to be in conflict with the current ASTM specifications and stateof-the-art mill practice In order to mitigate any potential conflict between Chapter material and the ASTM Specifications, it is proposed that these tables be moved into the Commentary where they may remain as a reference but will not cause a contractual problem Subcommittee 2 will continue to maintain the data in the tables and the date of the latest update will be provided as a note in each table as a caution to the user that there may be more current information available from ASTM Submitted by: M Kevin Moran, Chair SC B Revision of Manual Due Date: September 22, 2017 Revise Special Index; insert new Article 121b (re-numbering subsequent sub-articles); insert new Table and replace existing Tables , and with similar Tables , and (re-numbering subsequent Tables in Part 1 and Part 9); revise Article 13141; revise Section 14; revise existing Table (renumbered to ); revise Articles 142, 161, 162, 1641, 1643, 171, 173, 178, 1145, 521, 532 and 5321; revise notes of Figure ; and revise Articles 9121a, and as shown (additions shown in bold red underscore, deletions shown in bold red strikethrough, comments in brackets [ ] are explanatory text and are not part of final Manual text): Special Index High-strength structural steel 121b and Table Impact tests, FCM material 121b, 1145 and Table Impact tests, other than FCM material 121b and Table Notch toughness, FCM material 121b, 1145 and Table Notch toughness, other than FCM material 121b and Table Steel, structural 121b and Table Structural steel 121b and Table Structural steel, high-strength 121b and Table

2 Letter Ballot No MATERIALS ( ) 1 a The design requirements of these recommended practices, contained in this part are based on the use of materials conforming to the current requirements of the following ASTM specifications: Structural Steel Table A709, A36, A572(Grade 42 or 50), A588, A992 See also Table Where this material is to be used for applications in which improved notch toughness is important, such as welded main load carrying components subject to tensile stress other than Fracture Critical Members, defined in Article 1142, the impact test requirements of Table shall be met Notch toughness requirements for Fracture Critical Members shall be in accordance with Table Components requiring these toughness requirements shall be designated on the design drawings For bridge construction, the material shall not be rimmed or capped steel [covered by ASTM] Rivet steel see Part 7 and Appendix 1 High-strength bolts F3125, Grades A325 and A490 Carbon and Alloy Steel Nuts A563 Washers, Steel, Hardened F436 Direct Tension Indicators F959 High-Strength Twist Off Type Tension Control Bolts F3125, Grade F1852 Machine bolts A307 Cast steel A27, Grade or A148 Forged steel, for large pins A668 Welding electrodes See AWS D15 Article 122a [Insert new Article 121b and re-number subsequent sub-articles] b Where structural steel is to be used for applications in which improved notch toughness is important, such as welded main load carrying components subject to tensile stress: (1) For ASTM A709, the impact test requirements of the applicable A709 grade shall apply For FCMs (fracture-critical members) as defined in 1142, the grade shall be designated with the F suffix and a numeral indicating the applicable service temperature zone For other than FCMs, the grade shall be designated with the T suffix and a numeral indicating the applicable service temperature zone [2 nd and 3 rd sentence relocated from Tables] (2) For non-a709 steels, the impact test requirements, including energy, test temperature, and testing frequency, of the equivalent A709 grade as given in Table and applicable service temperature zone (see 121b(4)) shall be specified (3) Components requiring impact testing shall be designated on the design drawings or in the specifications (4) Service Temperature shall be taken to be the lowest ambient temperature expected for the area in which a structure is to be located or to which a structure is to be exposed while in service Zone 1 implies a minimum service temperature of 0 degrees F; Zone 2 implies a minimum service temperature of 30 degrees F; Zone 3 implies a minimum service temperature of 60 degrees F [relocated from Commentary]

3 Letter Ballot No [Delete existing Table and insert similar Table , re-numbering existing Tables through to through Delete existing Table and insert similar Table Insert new Table Re-number existing Tables through to through Re-number existing Table a to a Re-number existing Tables and to and (Not all re-numberings shown)] Table Impact Test Requirements for Non-A709 Structural Steel [Technical change: this is NOT limited to 4" as in the current Manual Currently left up to the designer to figure out what they want, but we extend other A709 requirements out past 4" when no other information is available, and that s probably what the Engineer would use for guidance anyway The Engineer may still specify something different in the contract documents This approach, do everything per A709, covers all aspects of testing which might be overlooked] ASTM Designation Equivalent ASTM A709 Grade for Impact Test Requirements Fracture-Critical Member (see 1142) Non-Fracture-Critical Member A36 Grade 36F Grade 36T A572, Grade 42 A572, Grade 50 Grade 50F Grade 50T A588 Grade 50WF Grade 50WT A992 Grade 50SF Grade 50ST [Re-number sub-articles due to insertion of new 121b] bc For the properties of steel cd Throughout this chapter, the equivalent materials of Table may be used interchangeably, subject to the additional requirements of Article 121a 121b A36 and A588 plate and bar over 4 inches in thickness have no equivalent A709 grade de A588/A588M material in thickness ef Material over 4 inches (100mm) in thickness shall not be used as a Fracture Critical Component fracture-critical component fg The design requirements

4 Letter Ballot No COMBINED STRESSES ( ) Axial Compression and Bending Members subject to both axial E = modulus of elasticity of the material F y = yield point of the material as specified in Table the applicable ASTM specification (see also Table ) [remainder of Article 1314 unchanged] SECTION 14 BASIC ALLOWABLE STRESSES The basic allowable stresses to be used in proportioning the parts of a bridge shall be as specified below When the allowable stress is expressed in terms of F y, F y = yield point of the material as specified in Table the applicable ASTM specification F u = lowest ultimate strength of the material as specified in Table the applicable ASTM specification (See also Table ) [Edit two entries to left column of existing Table (which will be renumbered to Table ) Right column values are unchanged] Bearing on pins F y = yield point of the material on which the pin bears, or of the pin material, as specified in Table whichever is less Bearing on F3125 Grade A325 and Grade A490 bolts L = Distance, inches, measured in the line of force from the center line of a bolt to the nearest edge of an adjacent bolt or to the end of the connected part toward which the force is directed d = Diameter of bolts, inch F u = lowest specified minimum tensile strength of the connected part, psi, as specified in Table WELD METAL ( ) 1 R(2008) See Table In the formulas, F y = yield point of base metal as specified in Table the applicable ASTM specification (see also Table ) [remainder of Article 142 unchanged]

5 Letter Ballot No COMPRESSION MEMBERS ( ) 1 R(2014) a Compression members shall be so designed that the main elements of the section are connected directly to the gusset plates, pins, or other members b In members consisting of segments connected by lacing or by solid cover plates, the thickness of the web plate, inches, shall not be less than b = unsupported distance between the nearest lines of fasteners or welds, or between the roots of rolled flanges, inches P c = allowable stress for the member of axial compression, psi, as determined by the applicable formula of Article 141 f = calculated stress in compression, psi F y = yield point, psi, as specified in Table the applicable ASTM specification for the material (see also Table ) c For the thickness 162 OUTSTANDING ELEMENTS IN COMPRESSION ( ) 2 R(2014) a The width of outstanding F y = yield point, psi, as specified in Table the applicable ASTM specification for the material (see also Table ) b The width of plates shall c Where a projecting element exceeds

6 Letter Ballot No LACING AND PERFORATED COVER PLATES FOR TENSION AND COMPRESSION MEMBERS ( ) 1 R(2014) 1641 Shear Force The shear force normal to A = member area required for axial compression, square inches (axial compressive force divided by allowable compressive stress) F y = yield point of member material as specified in Table the applicable ASTM specification (see also Table ) 1643 Perforated Cover Plates d For tension members yield point as specified in Table the applicable ASTM specification for the material (see also Table ), nor less [Remainder of Article 164 unchanged] 171 PROPORTIONING GIRDERS AND BEAMS ( ) 2 R(2014) a Plate girders, I-beams b Where the compression flange F y = yield point, psi, as specified in Table the applicable ASTM specification for the material (see also Table ) 173 THICKNESS OF WEB PLATES ( ) 2 R(2014) a The thickness of the P c = allowable stress in the compression flange, psi, as determined by the applicable formula of Article 141 f = the calculated extreme fiber stress in the compression flange, psi F y = yield point, psi, as specified in Table the applicable ASTM specification for the material (see also Table ) b The thickness of the webs c The thickness of the webs

7 Letter Ballot No WEB PLATE STIFFENERS (INTERMEDIATE TRANSVERSE AND LONGITUDINAL) ( ) 1 R(2014) a Where the depth of the t = thickness of web, inches S = calculated shear stress in F y = yield point, psi, as specified in Table the applicable ASTM specification for the material (see also Table ) [Remainder of Article 178 unchanged] 1145 NOTCH TOUGHNESS OF STEEL IN FRACTURE-CRITICAL MEMBERS ( ) 1 [add hyphen and change date in title] Charpy V-notch (CVN) impact test requirements for steels in FCMs shall be as given in Table except as shown in Note 6 Article 121b (see also Table ) [Delete existing Table and insert similar Table Re-number existing Tables and to and (Not all re-numberings shown)] 521 STRUCTURAL STEEL, BOLTS AND PINS ( ) 1 a Except as provided in b The allowable stress for steel bearing components is expressed in terms of F y or F u as specified in Article 5321, Table , Article 5322, Table , Table or, for the ASTM designations listed for Structural Steel in Article 121a, the applicable ASTM specification (see also Table ) [Remainder of Article 521 unchanged] 532 MATERIALS ( ) 1 Except as provided in Article 5321 through Article 5325 below, material for all bearing components produced from rolled steel plates or shapes, shall conform to one of the ASTM designations listed in Table for Structural Steel in Article 121a 5321 Pins, Rollers, and Rockers In addition to the designations listed in Table for Structural Steel in Article 121a, steel for pins, rollers, and [Remainder of Article 532 unchanged]

8 Letter Ballot No [Revise note 4 of Figure ] Notes: 1 Design, material and 2 Design, material and 3 Live Load: Superstructure - Alternate 4 Structural steel shall be one of the grades listed for Structural Steel in Article 121a and shall have a minimum yield stress of 36,000 psi and conform to Table [Remainder of notes unchanged] 9121 MATERIALS ( ) a Twist-Off Tension-Control Bolts: ASTM F1852 and F2280 bolts are tightened Twist-off bolts control When properly performed, F1852 bolts are F3125 Grade A490 bolts As a result of the increased Weathering Steel: Refer to Table , Note 2: ASTM A588 and A709, Grade 50W, Grade HPS 50W, and Grade HPS 70W have atmospheric corrosion resistance in most environments substantially better than that of carbon steels with or without copper addition In many applications, these steels can be used unpainted There is a potential for atmospheric corrosion rates to increase in applications that subject weathering grade steels to frequent alternating wet and dry or continuously moist conditions for prolonged periods of time; or to corrosive chemicals, including deicing salts Guidelines for proper application of unpainted weathering steels in bridges may be found in FHWA Technical Advisory T Uncoated Weathering Steel in Structures, dated October 3, 1989 [New material moved from Table] Impact Test Requirements for Structural Steel: Tables and Table make summarize provisions for materials with improved notch toughness ASTM A709, Grade HPS 70W and Grade HPS 50W steels have such high toughness that when they were included in the ASTM A709 Specification, the Zone 3 requirements, which are the most severe, were specified for all zones for both Non Fracture Critical, Table , and for Fracture Critical, Table Because of their high toughness it was decided to eliminate the need to choose the appropriate zone when using HPS 50W or HPS 70W and treat all zones alike Refer to Table and Table : Service Temperature shall be taken to be the lowest ambient temperature expected for the area in which a structure is to be located or to which a structure is to be exposed while in service The testing zones correspond with those chosen by AASHTO and imply the service temperatures listed in the tables Zone 1 implies a minimum service temperature of 0 degrees F; Zone 2 implies a minimum service temperature of 30 degrees F; Zone 3 implies a minimum service temperature of 60 degrees F

9 Letter Ballot No The service temperature zones defined in Article 121b(4) correspond with those chosen by AASHTO For guidance in determining the Lowest Anticipated Service Temperature for a particular location in the United States or Canada, Figure and Figure may be used Both figures show temperatures in degrees Fahrenheit Figure (US and Alaska) shows isolines for which there is a 99% chance that the daily minimum temperature will be no lower than shown Figure (Canada) shows isolines for which the temperature during January will be no lower than shown for 99% of the time Refer to Table : The recommended practice is silent on energy requirements for material thicker than 4 inches even though some of the materials listed are available in greater thicknesses Table will normally apply to welded main load carrying components subject to tensile stress and such applications will be rare for thicknesses exceeding 4 inches Nevertheless, if an engineer wishes to use a greater thickness, the notch toughness requirement for these materials not listed in Table should be specified [Insert new Tables , , and (similar to existing Tables , , and which are deleted by this ballot) preceding Figure Only major changes shown Metric equivalences deleted in Tables and ]

10 Letter Ballot No Table Structural Steel Strength (See Article 121a and Note 1) ASTM Designation F y Min Yield Point or Yield Strength psi F u Ultimate Tensile Strength or Tensile Strength psi A36 36,000 min (Note 2) 58,000 min 80,000 max (Note 3) A709, Grade 36 36,000 min 58,000 min 80,000 max (Note 3) Plates, shapes, and bars Applicability Plates up to 4 inches thick incl; shapes and bars A572, Grade 50 A709, Grade 50 50,000 min 65,000 min Plates up to 4 inches thick incl; shapes and bars A572, Grade 42 42,000 min 60,000 min Plates up to 6 inches thick incl; shapes and bars A588 50,000 min (Note 4) 70,000 min (Note 4) Plates up to 8 inches thick incl; shapes and bars A709, Grade 50W and Grade HPS 50W 50,000 min 70,000 min Plates up to 4 inches thick incl; shapes and bars A992 50,000 min 65,000 min Shapes A709, Grade 50S 65,000 max (Note 5) (Note 6) A709, Grade HPS 70W 70,000 min 85,000 min 110,000 max Plates up to 4 inches thick incl Note 1: This table summarizes for the designer s convenience the strength requirements of the referenced ASTM standards and is current as of December 2016 Note 2 Minimum F y = 32,000 psi for plate over 8 inches in thickness Note 3: For wide flange shapes with flange thickness over 3 inches, the 80,000 psi maximum tensile strength limit does not apply Note 4: For thicknesses over 4 inches to 5 inches incl, minimum F y = 46,000 psi and minimum F u = 67,000 psi For thicknesses over 5 inches to 8 inches incl, minimum F y = 42,000 psi and minimum F u = 63,000 psi Note 5: Maximum F y = 70,000 psi for structural shapes that are required to be tested from the web location Generally, web testing applies to all shapes except W and HP shapes with flanges 6 in or wider See ASTM A6 section 1132 and 1133 Note 6: Maximum F y/f u = 087 for shapes that are tested from the web location and 085 for all other shapes Generally, web testing applies to all shapes except W and HP shapes with flanges 6 in or wider See ASTM A6 section 1132 and 1133

11 Letter Ballot No Table ASTM A709 Impact Test Requirements for Structural Steel Other than Fracture-Critical Members (See Article 121b and Notes 1 and through 5 3) ASTM Designation Thickness, Inches (Note 4) Minimum Average Energy, Ft-lb, and Test Temperatures Zone 1 Zone 2 Zone 3 A36 All available 15@70 F 15@40 F 15@10 F A709, Grade 36T All available 15@70 F 15@40 F 15@10 F A992 To 2 incl 15@70 F 15@40 F 15@10 F A709, Grade 50ST A588 A572, Grade 42 A572, Grade 50 A709, Grade 50T Over 2 20@70 F 20@40 F 20@10 F A709, Grade 50WT (For all grades in this row, see Note 5) A709, Grade HPS 50WT All available 20@10 F 20@10 F 20@10 F (Note 5) A709, Grade HPS 70WT (Note 6) All available 25@-10 F 25@-10 F 25@-10 F Note 1: This table summarizes for the designer s convenience the impact energy requirements of ASTM A709 (or as applied per 121x to other steels) for non-fracture-critical main members in tension and is current as of December 2016 It does not cover every aspect of CVN testing given in ASTM A709 Note 52: Impact test requirements for structural steel of FCMs (fracture-critical members) are summarized in Table Note 13: Impact tests is at H (heat) frequency as defined in ASTM A673 for all grades except for A709, Grade HPS 70WT, which is P frequency Note 4: See Table for limitations on available thicknesses Note 25: If the yield point of the material as given in the test report exceeds 65,000 psi, the test temperature for the minimum average energy required is reduced by 15 F for each increment or fraction of 10,000 psi above 65,000 psi For example, if the yield point or yield strength is more than 65,000 psi but not more than 75,000 psi, the test temperature reduction is 15 F If the yield point or yield strength is more than 75,000 psi but not more than 85,000 psi, the test temperature reduction is 30 F [Examples were recently added in ASTM A709] Note 36: If the yield strength of the material as given in the test report exceeds 85,000 psi, the test temperature for the minimum average energy required is reduced by 15 F for each increment or fraction of 10,000 psi above 85,000 psi For example, if the yield point or yield strength is more than 85,000 psi but not more than 95,000 psi, the test temperature reduction is 15 F If the yield point or yield strength is more than 95,000 psi but not more than 105,000 psi, the test temperature reduction is 30 F

12 Letter Ballot No Table ASTM A709 Impact Test Requirements for Structural Steel Fracture-Critical Members ASTM Designation (See Articles 1145, 121b, and Notes 1 and 2) Thickness, In (Note 3) Minimum Test Value Energy Ft-lb Minimum Average Energy, Ft-lb and Test Temperatures Zone 1 Zone 2 Zone 3 A36 All available F 40 F 10 F A709, Grade 36F A992 To 2 incl F 40 F 10 F A709, Grade 50SF A572, Grade 50 A709, Grade 50F Over F 40 F 10 F A588 A709, Grade 50WF (For all grades in this row, see Note 4) A709, Grade HPS 50WF (Note 4) All available F 10 F F A709, Grade HPS 70WF (Note 5) All available F -10 F -10 F Note 1: This table summarizes for the designer s convenience the impact energy requirements of ASTM A709 (or as applied per 121x to other steels) for FCMs (fracture-critical members) and is current as of December 2016 It does not cover every aspect of CVN testing given in ASTM A709 Note 12: For shapes, impact testing is at P (plate frequency) as defined in ASTM A673 For plates, specimens are selected as follows: (1) As-rolled plates are sampled at each end of each plate-as-rolled (2) Normalized plates are sampled at one end of each plate-as-heat-treated (3) Quenched and tempered plates are sampled at each end of each plate-as-heat-treated Note 3: See Table for limitations on available thicknesses Note 24: If the yield point of the material as given in the test report exceeds 65,000 psi the test temperature for the minimum average energy required is reduced by 15 F for each increment or fraction of 10,000 psi above 65,000 psi For example, if the yield point or yield strength is more than 65,000 psi but not more than 75,000 psi, the test temperature reduction is 15 F If the yield point or yield strength is more than 75,000 psi but not more than 85,000 psi, the test temperature reduction is 30 F Note 35: If the yield strength of the material as given in the test report exceeds 85,000 psi the test temperature for the minimum average energy required is reduced by 15 F for each increment or fraction of 10,000 psi above 85,000 psi For example, if the yield point or yield strength is more than 85,000 psi but not more than 95,000 psi, the test temperature reduction is 15 F If the yield point or yield strength is more than 95,000 psi but not more than 105,000 psi, the test temperature reduction is 30 F Note 6: Steel backing for groove welds joining steels with a minimum specified yield strength of 50,000 psi(345 MPa) or less may be base metal conforming to ASTM A36/A36M, A709/A709M, A588/A588M or A572/A572M, at the Contractor s option, provided the backing material is furnished as bar stock rolled to a size not exceeding 3/8 in(10mm) by 1-1/4 in(32mm) The bar stock so furnished need not conform to the Charpy V-Notch impact test requirements of this table [Deleted covered in AWS D15] [Remainder of Article 9121 unchanged]

13 Letter Ballot No NOTCH TOUGHNESS OF STEEL IN FRACTURE-CRITICAL MEMBERS ( ) R(2008) For comments relating to Table specific grades of ASTM A709 see Article 9121 The notch toughness requirements a An understanding of the b An understanding of the c The development of a d Specification of CVN impact e A verification of the f An awareness of the extensive The safety and reliability Neither the AASHTO nor the The general difference in initiation [Figure unchanged] The use of impact or dynamic In summary, application of the The prime focus on Fracture Critical Members FCMs (fracture-critical members) must be on quality of the material and fabrication Using low fatigue resistant details should be avoided Category E and E details shall not be used on are prohibited for Fracture Critical Members FCMs, and Category D details shall be are discouraged and should be used only with caution PIECE MARKING ( ) Use of die stamps for There is no defined radius It is known that surface imperfections compromise fatigue performance of the otherwise smooth plate or rolled section However, experience demonstrates that die stamp marks are innocuous for steels in Table meeting fracture-critical toughness requirements (see Article 121b and Table ), particularly when precautions [Remainder of Article unchanged] WELDING INDEX Impact tests 121b, 1145 and Table Materials 121, 121b, and Tables and [End]