SECTION 1105 — FABRICATED STRUCTURAL STEEL
1105.01 GENERAL REQUIREMENTS —
References to Sections of Division II AASHTO Standard Specifications for Highway Bridges (date as indicated) are identified by the abbreviation AASHTO followed by the section number, e.g., AASHTO 188.8.131.52.
Unless otherwise specified, metal fabricators will be required to prequalify to perform work for the Department by establishing proof of their competency and responsibility, in accordance with the AISC Quality Certification Program. Registration and certification of the plant or shop under the AISC program, Category I, II, or III, and submission of a valid certificate to the Structural Materials Engineer, MTD, 1118 State Street, Harrisburg, Pennsylvania 17120, will be required by the Department. An annual endorsed copy will then be required for continued qualification.
Only fabricator having Category III with Certified Fracture Critical certification may fabricate the following:
Fracture critical members and attachments.
Only fabricators having Category III certification may fabricate the following:
Main members, except for rolled beams
Cross frames and diaphragms for curved bridges
Bracing, portals, and stiffening members for arches, trusses, cable-stayed and suspension bridges
Rolled beams with welding of any type, or which are heat curved or heat cambered.
Fabricators having Category I, II or III certification may fabricate the following:
Bridge drainage material
Rolled beams without welding
Cross frames and diaphragms for straight bridges*
Steel grid flooring
Shop-fabricated material for reinforcing existing bridges*
Lateral bracing except for arches, trusses, cable-stayed and suspension bridges*
Lighting poles and anchor bases
Welded sound barrier support
*Fabricate in a Category III shop if welding is required
**Fabricators of high load multi-rotational bearings are inspected by Structural Steel Engineers in the Structural Materials Section of the MTD to ensure that suitable machinery, machining ability, certified welders, and welding procedures are used before approval to fabricate bearings is given. AISC certification is not required.
AISC certification is not required for the following:
Castings, forgings and machined parts not welded
High load multi-rotational bearings
Material not requiring shop fabrication or shop welding, such as plates and shapes for strengthening existing bridges and manufactured items accepted by certification.
(b) Standard Reference.
Section 105.02 and as follows:
Bridge members are generally designed in lengths, depth and widths that can be transported from fabrication source to the project. Field splices, if required, are indicated. For shipping purposes, the addition of field splices to shorten members, or the elimination of field splices to lengthen members, will not be accepted on shop drawings without prior written acceptance by the District Engineer, in this case a sketch is required. Design computations prepared in accordance with Design Manual, Part 4, Structures and by a registered Professional Engineer may be required. The District Engineer will not review requests for elimination of field splices unless a notice is included from the TEOD, that a hauling permit can be obtained to ship beams exceeding the dimensions shown on the structure drawings.
(d) Erection Drawings.
The MTD will supervise shop inspection. Give ample notice of the beginning of work so that arrangements can be made for inspection.
The Engineer may waive shop inspection and make a complete inspection at a later stage in the construction sequence. Furnish certified mill reports, in duplicate, covering the structural steel used.
Facilities for Inspection.
Furnish necessary facilities for the inspection of material and workmanship. Allow inspectors employed by the Department unrestricted access to the premises during plant working hours. The necessary facilities for inspection include a plant office, as specified in Section 609 for Inspector's Field Office, Type C, except provide a four-drawer, fire-resistant (D-label) metal file cabinet in place of a two-drawer, fire-resistant (D-label) metal file cabinet.
Plant Inspector's Authority.
Plant Inspectors have the authority to reject any material or work not meeting the requirements of these specifications. In case of dispute, the Contractor may appeal to the Engineer, whose decision will be final.
Material, workmanship, or finished members accepted by the inspector at the shop may be rejected later if they do not conform to the specifications. Repair or replace rejected material or members.
If directed, furnish test specimens of material, as well as equipment, tools, and labor necessary to prepare the specimens and to make the tests.
Mill Orders and Shipping Statements.
Furnish copies of mill orders and shipping statements, as directed. Show the weights of the individual members on the statement, if directed. Assure that the fabricator presents the Department's shop inspector with a copy of the shipping invoice to be stamped for verification of inspection and approval of steel items prior to shipment. Forward the stamped copy with the shipment for the project file. Mill certifications will be reviewed, approved and returned to the fabricator by the shop inspector.
Storage of Materials.
Section 106.05 and as follows:
Place materials to be stored above ground upon platforms, skids or other supports. Place and support to avoid overstress, deformation or damage. Exercise special care for curved members. Keep material free from dirt, grease and other foreign materials and keep properly drained and protected from corrosion.
1105.02 MATERIAL —
(a) Structural Steel.
General Requirements for Delivery of Rolled Steel Plates, Shapes, Sheet Piling and Bars for Structural Use, AASHTO-M160 (ASTM-A6).
Use structural carbon steel unless otherwise specified.
2. Carbon Steel.
Use AASHTO-M270 (ASTM-A709), Grade 36, unless otherwise specified.
2.a Cold-Formed Welded and Seamless Carbon Steel Structural Tubing in Rounds and Shapes.
ASTM-A500, Grade C.
2.b Hot-Formed Welded and Seamless Carbon Structural Steel Tubing.
High Strength Low-Alloy Structural Steel for Welding.
3.a High-Strength Low-Alloy, Quenched and Tempered Structural Steel Plate.
AASHTO, Division II, Section 184.108.40.206.
3.b High-Strength Low-Alloy Structural Steel.
AASHTO-M270 (ASTM-A709), Grades 50 or 50W, of a quality suitable for welding.
3.c High-Strength Low-Alloy Columbium-Vanadium Steel of Structural Quality.
AASHTO-M270 (ASTM-709), Grade 50.
3.d High-Strength Low-Alloy Structural Steel with 50,000 psi Minimum Yield Point to 4 in. thick.
AASHTO-M270 (ASTM-A709), Grade 50W.
3.e High-Yield Strength, Quenched and Tempered Alloy Steel Plate.
3.e.1 High-Yield Strength, Quenched and Tempered Alloy Steel Plate, Suitable for Welding.
AASHTO, Division II, Section 11.3.1,5(a).
3.e.2 High-Strength Alloy Steel Plates, Quenched and Tempered, for Pressure Vessels.
ASTM-A517. Meet the supplementary notch toughness requirements specified for AASHTO-M244.
3.e.3 Quenched and Tempered Alloy Steel Structural Shapes and Seamless Mechanical Tubing.
AASHTO, Division II, Section 220.127.116.11(b).
Supplemental Requirements for Notch Toughness — Structural Steel: Meet the supplementary notch toughness requirements for the longitudinal Charpy V-notch tests specified for Zone 2, in Table S1 of the applicable AASHTO Materials Specifications. These supplemental requirements are mandatory for main load carrying member components subject to tensile stress, including:
Tension flanges of built-up beams
Beam splice material
Connecting plates for horizontal curved bridge members
Truss members and gusset plates attached to such truss members.
Diaphragms, X-frames, bracing, and connecting plates for straight girder bridges if the skew is less than 70 degrees, if the connections are welded, or if identified on the drawings as requiring notch toughness.
The requirements are not mandatory for:
Other secondary material
Diaphragms, X-frames, bracing, and connecting plates for straight girder bridges if the skew is more than 70 degrees, if the connections are bolted, or unless otherwise identified on the drawings as requiring notch toughness.
If directed at a prefabrication meeting, provide samples for Charpy V-notch testing from steel used in fabricating fracture critical plates and shapes. Submit the samples to the Structural Materials Engineer, MTD, 1118 State Street, Harrisburg, PA 17120. Obtain the samples from plates delivered to the fabricator.
(b) Bedding Material for Bridge Shoes.
(c) Bolts, Nuts, and Washers.
From a manufacturer listed in Bulletin 15 and as follows, unless otherwise indicated or specified:
1. Bolts and Nuts for General Application.
ASTM-A307, Grade A
2. Anchor Bolts.
AASHTO-M270 (ASTM-A709), Grade 36, anchor bolts (headed or nonheaded, either straight or bent) and cap screws
ASTM-A307, Grade A.
Federal Specification FF-W-92b dated May 9, 1974, Type A, Grade 1, Class A.
(d) High-Strength Bolts.
All bolts, nuts and washers are to be mechanically galvanized as specified in Section 1105.02(s), unless otherwise indicated or specified. Provide high-strength, carbon steel bolts; suitable nuts; and plain hardened washers for structural joints from a manufacturer listed in Bulletin 15, and, unless otherwise indicated or specified, meeting the following requirements:
For high-strength bolts, nuts, and washers to be used with AASHTO-M270 (ASTM-A709), Grade 50W steel, unpainted, conform to atmospheric corrosion resistance requirements equal to those of AASHTO-M270 (ASTM-A709), Grade 50W.
Conform to the identification markings and dimensions specified in AASHTO, Division II, Sections 18.104.22.168 and 22.214.171.124 respectively.
AASHTO-M164 (ASTM-A325), except as amended and revised herein.
Provide a lot number on the supplier's certification corresponding to that appearing on the shipping package and certification Form CS-4171. Note, on the supplier's certification, when and where all testing was done, including the rotational capacity tests specified, and include zinc thickness when galvanized bolts are used. Furnish bolts having diameters of from 1/2 inch to 1 inch inclusive, and a hardness of 24 to 33 HRC.
Provide black bolts "oily" to the touch when installed.
AASHTO-M292 (ASTM-A194) or AASHTO-M291 (ASTM-A563), as applicable.
Provide galvanized heat treated nuts; Grade 2H, DH, or DH3; and mechanically galvanized as specified in Section 1105.02(s) (AASHTO-M232 or AASHTO-M298).
Provide plain (ungalvanized) nuts which are Grade 2, C, D, or C3, having a Rockwell Hardness of 89 HRB; or heat treated, Grade 2H, DH, or DH3.
Lubricate all galvanized nuts with a lubricant containing a dye of any color that contrasts with the color of the galvanizing, so that a visual check can be made for the lubricant at the time of field installation.
Furnish nuts to be galvanized that are tapped oversize the minimum amount required to permit assembly on the bolt thread in the coated condition, and to meet the requirements of AASHTO-M291 (ASTM-A563) and the rotational capacity test specified.
AASHTO-M293 (ASTM-F436), galvanized, when indicated, as specified in Section 1105.02(s) (AASHTO-M232 or AASHTO-M298).
Direct Tension Indicator (DTI) Devices.
ASTM-F959 and as follows:
Provide Direct Tension Indicator (DTI) devices having a hardness of 38 to 45 HRC. Furnish plain DTI devices for use with plain bolts, and, when galvanized bolts are indicated or specified, provide galvanized DTI devices. Galvanize as specified in Section 1105.02(s) (ASTM-B695).
In addition to the bolt tension tests specified in ASTM-F959, test plain finish DTI devices a second time applying the compression load until the average gap measures 0.005 inch. Ensure that the loading remains within the acceptable range specified in Table 3 for the applicable type.
Ship each lot in protective containers marked with the type, lot number, quantity, and total lot size. Include a copy of the certification.
Certify, as specified in Section 106.03(b)3., that the lot conforms to ASTM-F959 and any additional requirements specified.
Handle and store DTI devices in accordance with the manufacturer's recommendations.
Obtain a minimum of 8 samples from each lot, in accordance with PTM No. 1, for testing at the MTD.
4.b Levels of Certification.
Use the same levels of certification specified in Section 701.1(b)2.; except, substitute the word "lot" for the word "silo".
Test bolts, nuts, washers, and assemblies as follows:
Perform proof load tests in accordance with ASTM-F606, Method 1, at the minimum frequency specified in AASHTO-M164 (ASTM-A325), Section 9.2.4.
Perform wedge tests on full size bolts in accordance with ASTM-F606, Section 3.5. If bolts are to be galvanized, perform testing after galvanizing. Use the minimum testing frequency specified in AASHTO-M164 (ASTM-A325), Section 9.2.4.
If galvanized bolts are supplied, determine the thickness of zinc coating by taking measurements on the wrench flats or top of bolt head.
Perform proof load tests in accordance with ASTM-F606, Section 4.2, at the minimum frequency specified in AASHTO-M291 (ASTM-A563), Section 9.3, or AASHTO-M292 (ASTM-A194), Section 126.96.36.199. If nuts are to be galvanized, perform testing after galvanizing, overtapping, and lubricating.
If galvanized nuts are supplied, determine the thickness of zinc coating by taking measurements on the wrench flats.
If galvanized washers are supplied, perform hardness testing after galvanizing. Remove the coating before taking hardness measurements.
If galvanized washers are supplied, measure the thickness of zinc coating.
Perform rotational-capacity tests on all black or galvanized bolt/nut/washer assemblies before shipping. Test galvanized assemblies after galvanizing. Washers are required as part of the test, even if they are not required as part of the installation procedure.
Except as modified herein, perform the rotational-capacity test in accordance with the requirements of AASHTO-M164 (ASTM-A325).
Perform a rotational-capacity test of long bolts or bolts too short to fit the tension calibrator in accordance with PTM No. 427.
Test each bolt production lot, nut lot, and washer lot in combination as an assembly. Where washers are not required as part of the installation procedure, they need not be included in the lot identification.
Assign a rotational-capacity lot number to each combination of lots tested.
Test a minimum of two assemblies per rotational-capacity lot.
The current AASHTO-M164 (ASTM-A325) requirement, that the test be performed on an assembly while being used in a steel joint, is superseded. Test the bolt/nut/washer assembly in a Skidmore-Wilhelm Calibrator or an equivalent acceptable device.
Report the results of all tests on the appropriate test report (including zinc coating thickness) as required in these specifications herein and in the applicable AASHTO or ASTM specifications.
Report the location where tests were performed and date of testing.
Tests need not be witnessed by an inspection agency; however, have the manufacturer or distributor performing tests certify that the results recorded are accurate.
Document test reports as follows:
6.a Mill Test Report (MTR).
Furnish a mill test report for all mill steel used in manufacturing bolts, nuts, or washers, and indicate where the material was melted and manufactured.
6.b Manufacturer Certified Test Report (MCTR).
Have the manufacturer of the bolts, nuts, and washers furnish a test report for each item furnished, and report the required information as specified.
Have the manufacturer performing the rotational-capacity test include the following on the MCTR:
The lot number of each of the items tested.
The rotational-capacity lot number, as required.
The results of required tests.
The location where tests were performed and date of testing.
Certification that the MCTR's for the items are in conformance with this specification and the applicable AASHTO or ASTM specifications.
The location where the bolt/nut/washer assembly components were manufactured.
6.c Distributor Certified Test Report (DCTR).
Have the distributor performing tests furnish a test report and include the following:
The MCTR for the various bolt/nut/washer assembly components.
The results of all required tests, including the rotational-capacity test if performed by the distributor in lieu of the manufacturer.
The location where tests were performed and date of testing.
The rotational-capacity lot number, as required.
Certification that the MCTR's are in conformance with this specification and the applicable AASHTO or ASTM specifications.
Welded Stud Shear Connectors.
AASHTO, Division II, Section 11.3.3.
(f) Steel Forgings and Steel Shafting.
1. Steel Forgings.
AASHTO, Division II, Section 188.8.131.52.
Cold-Finished Carbon Steel Shafting.
AASHTO, Division II, Section 184.108.40.206.
(g) Steel Castings.
1. Mild Steel Castings.
AASHTO, Division II, Section 220.127.116.11.
Chromium-Alloy Steel Castings.
AASHTO, Division II, Section 18.104.22.168.
3. Workmanship and Finish.
Make castings boldly filleted at angles, and the arrises perfect, true to pattern in form and dimensions, free from pouring faults, sponginess, cracks, blow-holes, and other defects in positions affecting the castings' strength and value for the service intended.
Defects not affecting the strength and value of the casting for the service intended may be corrected, if permitted in writing by the Chief Bridge Engineer. A blow-hole having a length greater than 1 inch, a cross-sectional area greater than 1/2-square inch, or a depth greater than 1/2-inch, or any group of holes in a straight line 1 foot long, measured on the surface of the casting, and whose gross length is greater than 1 inch, may be cause for rejection.
4.a Major Castings.
Test major castings by radiographing with x-ray or gamma ray apparatus, in accordance with ASTM-E186, E280 or E446, as applicable. See Table A. Major castings are those subject to high loading whose failure in service would cause major damage, e.g., bridge bearings or machinery parts in movable bridges. All castings over 1,000 pounds are major castings.
4.b Minor Castings.
Test minor castings by suspending them, then hammering them all over. Minor castings are those whose failure would not lead to failure of main bridge members, e.g., scuppers or gratings.
Cracks, flaws or other defects which appear during or after these tests may be cause for rejection.
(h) Iron Castings.
1. Gray Iron Castings.
AASHTO, Division II, Section 22.214.171.124(1).
Malleable Iron Castings.
AASHTO, Division II, Section 126.96.36.199(3).
3. Ductile Iron Castings.
AASHTO, Division II, Section 188.8.131.52(2).
4. Workmanship and Finish.
AASHTO, Division II, Section 184.108.40.206.
AASHTO, Division II, Section 220.127.116.11.
Severity Levels - Radiographically Inspected Castings*
E-466 up to 2"
E 186 2" to 4 1/2"
E 280 4 1/2" to 12"
* Radiograph all critical areas, but not less than 25% of each casting, or 25% of the castings, as shown on the drawings, and as accepted or directed.
** If unacceptable defects are found in more than 10% of the radiographs, radiograph 100% until the accumulated rejection level falls to 10% or less, at that time the testing may revert to 25%.
(i) Bronze Bearing and Expansion Plates.
Bronze Castings for Bridges and Turntables, AASTHO-M107 (ASTM-B22), Alloy No. C91100 or C91300, except that a maximum of 2 1/2% lead will be allowed, unless otherwise specified.
As indicated, make surfaces permanently self-lubricated, to provide a coefficient of friction of less than 0.10, or as indicated.
1. Pipe and Couplings.
Pipe, Steel, Black and Hot-dipped, Zinc-coated, Welded, and Seamless, ASTM-A53.
Flanges and Pipe Fittings.
Malleable Iron Flanges, Pipe Fittings, and Valve Parts for Railroad, Marine, and Other Heavy-Duty Service at temperatures up to 650F, ASTM-A338.
3. Welded Fittings.
Piping Fittings of Wrought Carbon Steel and Alloy Steel for Moderate and Elevated Temperatures, ASTM-A234.
4. Threaded Parts.
Immediately before assembly, apply one coat of dull red primer to all threads, then wipe clean after assembly.
(k) Low-Alloy Steel Pipe.
1. Pipe and Couplings.
Manufactured from low-alloy steel AASHTO-M270 (ASTM-A709), Grades 50 or 50W, Type 2 or AASHTO-M270 (ASTM-A709) Grade 50W, and otherwise conforming to Welded and Seamless Steel Pipe, ASTM-A53, or conforming to High-Strength Low-Alloy Welded and Seamless Steel Pipe, ASTM-A714, Class 4, Grade V.
Flanges and Pipe Fittings.
Malleable Iron Flanges, Pipe Fittings, and Valve Parts for Railroad, Marine, and Other Heavy-Duty Service at Temperatures up to 650F, ASTM-A338.
3. Welding Fittings.
Factory-Made, Wrought Carbon Steel and Derritic Alloy Steel Welding Fittings, ASTM-A234.
4. Threaded Parts.
Immediately before assembly, apply one coat of dull red primer to all threads, then wipe clean after assembly.
(m) Steel Tubing.
Cold-Formed, Welded and Seamless Carbon Steel Structural Tubing in Rounds and Shapes, ASTM-A500, or Hot-Formed, Welded and Seamless Carbon Steel Structural Tubing, ASTM-A501.
(n) Cast Iron Pipe.
Cast Iron Soil Pipe and Fittings, ASTM-A74, or Gray Iron and Ductile Iron Pressure Pipe, ASTM-A377.
(p) Sheet Copper.
Copper Sheet, Strip, Plate, and Rolled Bar, AASHTO-M138 (ASTM-B152), and meeting the requirements of the Embrittlement Test, Section 11 of AASHTO-M138 (ASTM-B577).
Make lapped joints by soldering or by riveting and soldering.
Rolled Zinc, ASTM-B69, Type II.
Make lapped joints by soldering.
(r) Sheet Lead.
Common Desilverized Lead A, as specified for Pig Lead ASTM-B29.
From a galvanizer listed in Bulletin 15 and as follows:
When indicated or specified, galvanize materials conforming with the applicable material specifications or, in case the particular material specification does not include galvanizing, galvanize in accordance with ASTM-A53; ASTM-B633; ASTM-A392, Class 2 coating; ASTM-B695 and B696 (AASHTO-M298 and M299); ASTM-A123 (AASHTO-M111); or ASTM-A153 (AASHTO-M232), as applicable.
Test for the specified weight of galvanizing in accordance with ASTM-A90 (AASHTO-T65).
Comply with ASTM-A143 and ASTM-A385.
2. Repair of Damaged Galvanizing.
After erecting galvanized material in place, clean damaged areas and apply two coats of Zinc Dust — Zinc Oxide Paint, Bulletin 26, or other acceptable material.
Conform to the requirements of the ANSI/AASHTO/ AWS D1.5-88 Bridge Welding Code with modifications as specified in Section 1105.03(m)1.
AASHTO, Division II, Section 18.104.22.168.
1105.03 FABRICATION —
Straightening Material and Curving Rolled Beams and Welded Girders.
AASHTO, Division II, Sections 11.4.7 and 11.4.12.
Finish exposed work. Shear, flame cut, and chip carefully and accurately. Make sharp corners and round edges by grinding or by other means.
When AASHTO-M270 (ASTM-A709), Grade 50W steel is specified for beams or girders, blast clean only the fascia side of exterior beams or girders in the field. Blast clean from the top outside (fascia) edge of the top flange to the inside edge of the bottom flange including bottom of the bottom flange, in accordance with SSPC-SP6-85 - Commercial Blast Cleaning.
(c) Bolt Holes.
AASHTO, Division II, Section 11.4.8.
(d) Preparation of Field Connections.
AASHTO, Division II, Section 22.214.171.124.
Accuracy of Hole Group.
AASHTO, Division II, Section 126.96.36.199.
AASHTO, Division II, Section 11.5.1.
(g) Preassembly of Field Connections.
AASHTO, Division II, Section 11.5.3, except use Progressive Truss or Girder Assembly, unless otherwise specified in the proposal.
AASHTO, Division II, Section 11.5.4.
(i) Connections Using Unfinished, Turned or Ribbed Bolts.
AASHTO, Division II, Section 11.5.5 except without ribbed bolts.
(j) Connections Using High Strength Bolts.
AASHTO, Division II, Section 11.5.6, except without ASTM-A490 bolts.
(k) Plate Cut Edges.
AASHTO, Division II, Section 188.8.131.52.
AASHTO, Division II, Section 11.5.7 except:
Refer to the ANSI/AASHTO/AWS D1.5-88 Bridge Welding Code for welding of structural steel for highway bridges in its entirety with the following modifications:
Section 1.1.3 Revise the second sentence to read: The term Engineer will be used, and it is to be construed to mean the Chief Bridge Engineer or the Chief Bridge Engineer's representative; namely, the Chief Structural Materials Engineer.
Section 1.3.2 Delete this section.
Section 2.3.3 Plug and Slot Welds. Delete this section.
Section 2.8 Details of Plug and Slot Welds. Delete this section.
Section 4.1.6 Delete this section.
Table 4.2 Matching Filler Metal Requirements for Welding Procedures Qualified in Accordance with the Provisions of 5.7. Delete all references to electroslag and electrogas welding.
Section 4, Part E, Electroslag and Electrogas Welding. Delete this part.
Section 4, Part F, Plug and Slot Welds. Delete this part.
Section 184.108.40.206 Electroslag and Electrogas Welding. Delete this section.
Section 220.127.116.11 Delete this section.
Do not weld to flanges in tension areas unless indicated in the contract.
Show types of steel on shop drawings.
Do not weld temporary fabrication and construction details; such as rails for deck finishing equipment, bar supports, or deck-forming devices; to beams, girders, or other main members, unless accepted by the Engineer. Identify locations of such welds on the shop drawings.
Do not use electroslag or electrogas welding.
Do not use gas metal arc welding process (GMAW), or flux cored arc welding (FCAW) for main load-carrying members, e.g.: rolled shapes; web-to-web welds; web-to-flange welds; flange-to-flange welds; stiffener and connection plate welds to flanges or webs, truss members, or gusset plates. The GMAW and FCAW processes may be used for welding drainage material, expansion dams, X-frames, diaphragms, bearings, bracing, and other secondary material, unless otherwise indicated.
Do not use plug welds to repair misplaced holes.
Non-destructively test all groove welds in main members in accordance with ANSI/AASHTO/AWS D1.5-88 Bridge Welding Code. Unless otherwise specified, use radiographic testing on butt joints. Use radiographic or ultrasonic testing for corner or "T" joints. Use magnetic particle testing for all stiffener to flange fillet welds.
Oxygen and Air Plasma Arc Cutting.
Steel and weld metal may be oxygen cut or air plasma arc cut. For oxygen cutting, refer to ANSI/AASHTO/AWS D1.5-88 Bridge Welding Code, as indicated, and with modifications as specified in Section 1105.03(m)1. Apply the same specifications on workmanship to the air plasma arc process. This process may be used to cut AASHTO-M270 (ASTM-A709), Grades 36, 50 and 50W materials up to 1/2-inch thick. Do not use if it involves applying water to the base metal.
For fabrication of non-redundant fracture critical bridge members refer to the applicable edition of AASHTO Guide Specifications for Fracture Critical NonRedundant Steel Bridge Members.
Facing of Bearing Surfaces.
AASHTO, Division II, Section 11.4.6 and as follows:
Add the following to the list of bearings, base plates, and other bearing surfaces in AASHTO, Division II, Section 11.4.6:
Sliding bearings — Stainless ANSI 5
Steel to Polytetrafluoroethylene (No. 8 Bright Mirror Finish)
Fabricate bearing surfaces to meet the following additional requirements:
Machine sliding bearings, having a surface roughness of ANSI 60 or rougher, so the lay of the cut is parallel to the direction of movement.
Provide machined surfaces plane and true, conforming accurately to the indicated dimensions.
For surfaces designed to be flat, machine surfaces to within 0.01 inch of flatness. Determine flatness as specified in Section 1111.03(c).
Maintain uniform, even contact when assembling adjacent bearing surfaces. Do not exceed a gap of 0.040 inch between bearing surfaces unless a closer tolerance is specified. Machine all sliding surfaces of base plates.
Do not machine any surfaces of fabricated members until all fabrication and welding of the assembly or subassembly is complete. Machine heat-treated components after completion of heat treating.
(q) Abutting Joints.
AASHTO, Division II, Section 11.4.5.
Plates: Direction of Rolling. Fabrication of Members.
AASHTO, Division II, Section 18.104.22.168 and as follows:
Unless otherwise indicated or specified, fabricate I-shaped beams and girders so the web is vertical under its own weight when erected, within allowable tolerance. Provide flanges normal to the web, unless otherwise indicated.
(s) Bent Plates.
AASHTO, Division II, Section 22.214.171.124.
Fit of Stiffeners.
AASHTO, Division II, Section 11.4.4 and as follows:
Tight fit, unless welding is indicated or specified. Mill or grind the ends of bearing stiffeners so that they have full bearing on the flange through which they transmit concentrated loads or reactions.
AASHTO, Division II, Section 11.4.10.
(x) Annealing and Stress Relieving.
AASHTO, Division II, Section 11.4.11.
(z) Pins and Rollers.
AASHTO, Division II, Section 11.4.9.
(aa) Boring Pin Holes.
AASHTO, Division II, Section 126.96.36.199.
Threads for Bolts and Pins.
AASHTO, Division II, Section 188.8.131.52.
Full Size Tests.
AASHTO, Division II, Section 11.4.14.
Marking and Shipping.
AASHTO, Division II, Section 11.4.15.
Section 1060.3 and as follows:
Include, on the shipping papers, the manufacturer of the complete self-curing inorganic zinc system consisting of the primer, intermediate tie, and finish
(ff) Identification of Steel During Fabrication.
AASHTO, Division II, Section 11.4.1 and as follows:
Use low stress steel stamps for die stamping material.
(gg) Welded Connections.
AASHTO, Division II, Section 11.5.2.
(hh) Numerically-Controlled Drilled Field Connections.
AASHTO, Division II, Section 184.108.40.206.
(ii) Facing of Bolted Surfaces.
ASTM-A6, and as follows:
Provide surfaces plane and true, within the specified tolerances.
Variations for surfaces designed to be flat: Conform to ASTM-A6, Tables 13, 14, and 15, unless otherwise specified.
Complete all welded attachments to bolted surfaces, before machining surfaces to required tolerances.
Grinding is only permitted on surfaces less than 2 inches wide, or as otherwise approved by the Engineer.
Use milling or other acceptable procedures to correct plate flatness tolerances.
Provide plate thickness as indicated. Identify each plate and the methods used to correct plate flatness not meeting specified tolerances.
Replace rejected plates at no additional cost to the Department.
(jj) Determination of Surface Flatness.
Furnish surfaces having flatness as determined by the following method:
Place a precision straightedge, that is a minimum of 6 inches longer than the surface to be measured, in contact with and as parallel as possible to the surface to be measured.
Select a feeler gage having the required tolerance, and attempt to insert it under the straightedge during the measurements.
Flatness is acceptable if the feeler gage does not pass between the straightedge and the surface.
In determining flatness, the straightedge may be located in any position on the surface being evaluated and not necessarily at 90 degrees to the edge.
Most Current Supplement
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