541Steel Structures

541.1 Description

This Work consists of providing , fabricating, erecting, and coa ting Structural Steel. Structural Steel includes forged or cast steel, bolts, tie rods , other ferrous or nonferrous Materials, and miscellaneous st eel. Steel shall be divided int o the following categories: Tier 1 – rolled steel beams, plate girders, diaphragms and cross fram es for steel Bridges, and overhead sign Structures. Tier 2 – metal Bridge barrier rails, di aphragms for concrete Bridges, and steel bearing components. Tier 3 – drop inlets, safety grates, cattle and game guards, pedestri an rails, gates, access panels, and other miscellaneous steel. For welding of driven pile splic es, see Section 541.3.6.4, “Fie ld Welding.”

541.2 Materials

541.2.1 Structural Steel

The Contractor shall provide Structural Steel in accordance wit h AASHTO M270, Grade 50, unless otherwise designated in the Contract. The Contracto r shall provide steel for anchor bolts, sole plates, minor Bridge components, inlet grates, and cattle guards in accordance with AASHTO M270, Grade 36 or Grade 50.

541.2.1 1 Impact Testing Requirements for Non-Fracture-Critical Structures

For Materials requiring impact testing, the Contractor shall no t weld repair the base metal at the producing mill. The Department will consider Structures to be non-fracture-critical, unless otherwise designated in the Contract. The Contractor sh all fabricate the following in accordance with AASHTO M270, Table 10 when subject to tensile s tresses: 1. Wide flange beams used as m ain load carrying members; 2. Flanges and web plates used in plate girders; 3. Flange cover plates; 4. Flange and web splice plates; and 5. Other components designated in the Contract. The Contractor shall conduct Charpy V-notch (CVN) impact “H” or “P” frequency testing in accordance with AASHTO T243. The Contractor shall ensure that Structural Steel meets require ments for minimum service temperatures as described for Zone 2 of the AASHTO’s Standard Specifications for Highway Bridges (negative one degrees (–1°)F – 30°F). The Contractor shall conduct plate-frequency testing instead of hat-lot testing for plate Material thicker than 1-1/2inch.

541.2.1 2 Impact Testing Requirements for Fracture-Critical Bri dge Components

Section 541: Steel Structures Page 489 The Contract will specify the CV N requirements for fracture-cri tical Bridge components.

541.2.2 Shear Connector Studs

The Contractor shall provide shear connector studs fabricated f rom cold-drawn bars, grades 1015, 1018, or 1020, either semi-killed or fully-killed in accordance with AASHTO M169. If using flux-retaining caps, the Contractor shall use the low carbon grade steel for the caps that is suitable for welding and in accordance with ASTM A 109. The Contractor shall produce the finish by cold drawing, cold rolling, or machining. The Contractor shall ensure stud tensile properties are in acco rdance with Table

541.2 2:1, “Tensile Properties of Shear Connector Studs,” as de termined by tests of bar stock

(after drawing) or finished studs, in accordance with ASTM A370 . Table 541.2.2:1 Tensile Properties of Shear Connector Studs Property Minimum Requirement Tensile strength 60,000 psi Yield strength @ 0.2% offset 50,000 psi Elongation in two (2) inch 20% Reduction of area 50% The Contractor shall weld studs with automatic stud welding gun s that shall be used to weld studs to girders. The operator shall be qualified per AWS D1.5 Subsection 7.7.4. The base metal where the stud is to be welded shall be ground to br ight metal immediately prior to the weld being made. Manual welding will not be allowed except to make repairs. Repairs shall be in accordance with AWS D 1.5 Subsection 12.6. Repair f illet size shall be a minimum of 5/16 inch.

541.2.3 Aluminum

The Contractor shall provide aluminum and aluminum alloy Materi als in accordance with ASTM aluminum alloy designation and in accordance with the Plan s.

541.2.4 Bolts

The Contractor shall provide hi gh-strength bolts in accordance with Section 542, “High- Strength Bolts.” The Contractor shall provide other bolts in a ccordance with ASTM A307, Grade A.

541.2.4 1 Unfinished Bolts

The Contractor shall provide unfinished ASTM A307 bolts. The C ontractor shall provide thread bolts so that not more than two (2) threads are within t he grip of the connected parts. The Contractor shall use bolts that will extend beyond the nut at least two (2) threads, but not more than 1/2 inch.

541.2.5 Structural Steel Coating

The Contractor shall provide coated Structural Steel in accorda nce with Table 541.2.5:1, “Coating of Structural Steel.” Table 541.2.5:1 Coating of Structural Steel Item Coating Requirement Galvanizing, Hot-Dip Galvanizing, or Zinc Coating Section 541.2.5.1 Structural Steel for Steel Bridges Section 544, “Protective Coating of New Structural Steel” Structural Steel for Concrete Bridges Section 544, “Protective Coating of New Structural Steel” Structural Steel for Miscellaneous Structures Section 545, “Protective Coati ng of Miscellaneous Structural Steel” Metal Bridge Railing Section 545, “Protective Coati ng of Miscellaneous Structural Steel” New Exposed Steel Bridge Piling and Similar Applications Section 545, “Protective Coati ng of Miscellaneous Structural Steel” Recoating Bridges Section 546, “Recoating Structures”

541.2.5 1 Galvanizing or Zinc Coating

If the Contract requires a galvanized coating, the Contractor s hall coat steel after fabrication in accordance with AASHTO M111. Bolts, washers, nuts, and position dowels used in the assembly and erection of galvanized railing and posts or wh ere specified, shall be galva nized in accordance with AASHTO M232 Class C or shall be zinc coated in accordance with ASTM B695. After erecting the steel, the Contractor shall coat the galvani zed hardware with a product meeting ASTM A780, Type 2.

541.2.5 1.1 Quality Control and Repair of Galvanizing

Uncleaned slag lines, bare spots, b listers, flux spots or inclu sions, dross, acid, or black spots that exceed one (1) square inch or occur on more than fiv e percent (5%) of the exposed surface area shall be cause for rejection of the lot. The Mate rials may be stripped, regalvanized, and again submitted for inspection; otherwise the entire lot shall be rejected. Pieces with damage to less than five percent (5%) of the expose d surface area may, with the approval of the Project Manager, be repaired in accordance with ASTM A780 Type 1 - zinc-based solders which includes low melting point zinc alloy repair rods or powders or Type 3 - metallizing. With the approval of the Project Manager, on areas that are con cealed from direct weathering and on areas that are not aesthetically visible to t he travelling public, ASTM A780 Type 2 (paints containing zinc dust, commonly referred to as “c old galvanizing”) may be used on areas less than one square inch and less than five percent ( 5%) of the exposed surface area. The dried film must contain no less than 90% pure zinc. Surface preparation and application shall be in accordance with the manufacturer’s requ irements. Section 541: Steel Structures Page 491 In any case, galvanizing repair shall not compromise the aesthe tic Acceptability of the Project as determined by the Project Manager.

541.3 Construction Requirements

541.3.1 Applicable Codes and Documents

The Contractor shall fabricate and erect steel Structures in ac cordance with the current edition of the following codes and documents: 1. AASHTO/AWS D1.5 – Bridge Welding Code ; 2. AASHTO/AWS D1.1 – Structural Welding Code ; 3. AWS D1.4 – Structural Welding Code – Reinforcing Steel ; 4. AISC 204 – AISC Certification Program for Bridge and Highway Metal Component Manufacturers; and 5. The following AASHTO/NSBA Steel Collaboration documents: 5.1. S2.1 Steel Bridge Fabrication Guide Specification; 5.2. S 4.1 Steel Bridge Fabricat ion QC/QA Guide Specification; 5.3. S10.1 Steel Bridge Erection Guide Specification; 5.4. G 1.1 Shop Detail Drawing Review / Approval Guidelines; 5.5. G 1.3 Shop Detail Drawing Presentation Guidelines; and 5.6. G12.1 Guidelines to Design for Constructability . Although the AASHTO/AWS Steel Collaboration documents are titl ed “Guidelines” or “Guide Specifications,” consider them to have the same importan ce and standing as a code or a Specification. If the content of the collaboration documents appears permissive with words such as “should,” “could,” “may,” etc., consider the content to be a requirement unless otherwise approved by the State Bridge Engineer. In the event of a conflict between a referenced code and this Specification, this Specification will take precedence. In AASHTO/NSBA Steel Bridge Collaboration S 4.1, all references to Quality Assurance Inspector (QAI) shall be equival ent to referencing the Project Manager.

541.3.2 Quality Control and Quality Assurance (Contractor)

Quality Control and Quality A ssurance shall be in accordance wi th the following: Tier 1 – AASHTO/NSBA Steel Bridge Collaboration, S 4.1 Steel Bridge F abrication QC/QA Guide Specification. Tier 2 – NMDOT Approval of fabrication shop is required, AISC Certifi cation Program for Bridge and Highway Metal Component Manufacturers (AISC 204) cur rent edition shall be used as the basis for approval (AI SC Certification is not requi red). Tier 3 – NMDOT Approval of fabrication shop is required, AISC Certifi cation Program for Bridge and Highway Metal Component Manufacturers (AISC 204) cur rent edition shall be used as the basis for approval (AI SC Certification is not requi red). Fabricators shall contact the State Bridge Engineer to request shop inspection and approval.

541.3.2 1 Qualification of QA Inspector (NMDOT Representative)

Tier 1 – AASHTO/NSBA Steel Bridge Collaboration, S 4.1 Steel Bridge F abrication QC/QA Guide Specification, Part C is superseded by the followin g requirement: current AWS Welding Inspector Certification. Tier 2 – Licensed Professional Engineer or a certified AWS Welding In spector. Tier 3 – Project Manager or a certified AWS Welding Inspector. The individual qualified for steel inspection shall also perfor m coating inspections with no further qualification with the exception of Tier 2 which may be performed by the Project Manager or certified AWS Welding Inspector. AASHTO/NSBA Steel Bridge Collaboration, S 4.1 Steel Bridge Fabrication QC/Q A Guide Specification 3.2 and 8.1.2 shall not apply to the QAI inspector of coatings.

541.3.3 Submittals

For Tier 1, prior to installation, the Contractor shall provide all submittals in accordance with Section 106, “Control of Materials.” Additional required submittals follow but are not limited to: 1. Structural Steel Mill Test Reports (MTRs); 2. Certificates of Compliance and other documentation for the p rotective coating; 3. The manufacturer’s Certificate of Compliance for welding con sumables; 4. QC inspection reports; and 5. A general Certificate of Compliance for the fabricated produ ct. The Contractor shall submit Certificates of Compliance instead of MTRs for Materials subjected to minimal stress leve ls, such as sole plates, shoe p lates, anchor bolts, and fill plates.

541.3.3 1 Working Drawings

The Contractor shall allow 30 Days for review and Acceptance of Working Drawings and calculations. Any re-submitta ls will require an additional 14 D ay s f o r r e v i ew . Th e W o r k i n g Drawing submittal process must be complete prior to the Pre-Fab rication Conference (Section

541.3.5 1, “Pre-Fabrication Conference”).

The Contractor shall prepare Working Drawings in accordance wit h AASHTO/NSBA G 1.3, Shop Detail Drawing Presentation Guidelines. The Departme nt will review Working Drawings for Acceptance in accordance with AASHTO/NSBA G 1.1, S hop Detail Drawing Review / Approval Guidelines. T he Working Drawing submittal sh all include a detailed bill-of- Material in accordance with AASHTO/NSBA Steel Bridge Collaborat ion G 1.1 with the letter of intent to fabricate. The Contractor shall submit Working Drawi ngs electronically in PDF format to the Project Manager. The Contractor shall not make any changes to Accepted Working D rawings. If changes are made, the Contractor shall re -submit the Working Drawings f or Acceptance. The Contractor shall include the submittal and review time for its shop drawings and schedule for fabrication of the specialized structural steel co mponents as a milestone per Section 108.3.1.1, “CPM Baseline Schedule” (bullet 5).

541.3.3 2 Working Drawings for Structural Steel Items Detailed on Standard Drawings

The Contractor may submit standar dized Working Drawings instead of Project-specific drawings for Structural Steel i tems such as cattle guard grills and drop inlet grates. The Contractor shall include the Fabricator’s name and address, drawing title, drawing number, drawing date, revision dates, and Standard Drawing numb er on Working Drawings.

541.3.3 3 Erection Plan

The Contractor shall submit an erection Plan for Tier 1 steel. Erection Plans are not required for OH Sign Structures. The Contractor shall submit an Erection Plan conforming to Sect ion 2 of the AASHTO/NSBA Steel Bridge Erection Guide Specification S10.1, 20 14 Edition and the following Department requirements: 1. The Erection Plan shall be prepared by a Professional Engine er licensed in the State of New Mexico and shall be accompanied by calculations ve rifying the safety of all aspects of erection; 2. The Erection Plan shall consi der the load-bearing capacities of any temporary or permanent Structures used in the erection of the new Bridge, in cluding any need for shoring; 3. The Erection Plan shall be submitted no less than thirty (30 ) Days prior to any steel erection operations; and 4. All costs for the Erection Plan and shoring of any temporary or permanent Structure used for the erection of the new Bridge shall be considered inc luded in Bid Item 541100 – Structural Steel for Steel Bridges. The Contractor shall allow 30 Days for review and Acceptance of the erection Plan. Any re-submittals will require an additional 14 Days for review. T he erection Plan submittal process must be complete prior to the start of erection. The Contractor shall include the submittal and review time for its erection Plan and schedule for erection of the spec ialized structural steel compo nents as a milestone per Section 108.3.1.1, “CPM Baseline Schedule” (bullet 5).

541.3.4 Rolled Girders and Plate Girders

The Contractor shall provide girders to the full length shown in the Plans. Bolted or welded girder splices will not be permitted unless noted otherw ise in the Plans.

541.3.5 Fabrication

The Contractor shall ensure that the fabrication shop for Tier 1 steel is certified in accordance with AASHTO/NSBA Steel Collaboration S2.1 , Steel Bridge Fabrication Guide Specification . The Department will not require AISC certification for fabri cation shops fabricating Tier 2 and Tier 3 steel items, but the Department m ust inspect and approve these shops before fabrication. Steel will be fabricated in the shop unless otherwise approved by the Project Manager. Tier 1 – AASHTO/NSBA Steel Bridge Collaboration, S2.1 Steel Bridge Fa brication Guide Tier 2 – AISC Certification Program for Bridge and Highway Metal Comp onent Manufacturers (AISC 204) current edition. Tier 3 – AISC Certification Program for Bridge and Highway Metal Comp onent Manufacturers (AISC 204) current edition.

541.3.5 1 Pre-Fabrication Conference

A Pre-Fabrication Conference is required for Tier 1 steel (a Pr e-Fabrication Conference is not required for OH Sign Structures). The Pre-Fabrication Conf erence shall be held in conjunction with the Pre-Constr uction Conference. The Pre-Fabr ication Conference may be held on an alternate date at the discretion of the Project Mana ger. The agenda for the Pre- Fabrication Conference shall be based upon S2.1, “Steel Bridge Fabrication Guide Specification.”

541.3.5 2 Attachment and Fit of Gussets and Stiffeners

Where welding of gusset plates, stiffeners or other secondary a ttachments to main structural members would otherwise result in intersections of w elds, the Contractor shall clip back the corners of the attachments 1-1/4 inch minimum from the corner in each direction to avoid such intersections. The Contractor shall terminate welds attaching secondary compon ents to main members 1/4 inch short of the end of the attachments. If the Plans require bearing stiffeners “finished to bear,” the Contractor shall mill or grind the ends and obtain an even bearing against the flange the stif feners will bear on. If the Plans require “tight fit” stiffeners, the Contractor sha ll fit the stiffeners tight against the flange to exclude water after being coated.

541.3.5 3 Straightening of Flanges

At pier bearings, abutment bearings and splices, the Contractor shall straighten girder or beam flanges perpendicular to the webs. At bearings, the Contr actor shall straighten flanges before fitting stiffeners. At splices, the Contractor shall st raighten flanges before coating and shipment. The Contractor shall not cold bend.

541.3.5 4 Bearing Plates, Pins, and Rollers

541.3.5 4.1 Sole, Masonry, and Shoe Plates

The Contractor shall flatten the top and bottom surfaces of sol e masonry and shoe plates to within ± 1/32 inch. The Contractor shall machine sole plate surfaces that will cont act elastomeric bearing pads perpendicular to the direction of expansion. The Contractor shall machine ot her expansion surfaces in the di rection of expansion.

541.3.5 4.2 Pins and Rollers

Section 541: Steel Structures Page 495 The Contractor shall accurately turn pins and rollers to dimens ions and ensure that they are smooth, straight, and free of flaws.

541.3.5 4.3 Pin Holes

The Contractor shall bore a two (2) inch diameter hole longitud inally through the center of pins with an eight (8) inch diameter or larger. The Contractor shall bore pinholes true to the specified diamet er, smooth and straight, at right angles to the axis of the member and parallel with each o ther unless otherwise required. The Contractor shall produce the final surface with a finishing cut. The Contractor shall not vary the outside to outside distance o f end holes in tension members and inside to inside distance of end holes in compressi on members by more than 1/32 inch. The Contractor shall bore holes in built-up members after shop assembly.

541.3.5 4.4 Threads

The Contractor shall ensure that bolt and pin threads are in ac cordance with Unified Standard Series UNC-ANSI B1.1, Class 2A for external threads an d Class 2B for internal threads. The Contractor shall thread pin ends with a diameter of 1 3/8 inch or greater with six

541.3.5 4.5 Surface Finish

The Contractor shall finish the surfaces of bearings, base plat es, pins, rollers, and other bearing steel that will come into contact with each other or wi th concrete in accordance with ANSI B46.1, Surface Roughness, Waviness and Lay.

541.3.5 5 Connections

541.3.5 5.1 Welding

541.3.5 5.1.1 Welder Qualifications

The Contractor shall use annually certified welders or those wh o provide documentation demonstrating continuing experie nce in the process. Welder mus t be qualified for the position the weld is performed in. All welders shall be certified by AA SHTO/AWS D1.1 or D1.5 unless otherwise noted in the Contract. Tier 1 – AASHTO/NSBA Steel Bridge Collaboration, S2.1 Steel Bridge Fa brication Guide Specification (Built-up plat es and open rolled-shape structural elements AWS D1.5, welded tubular structural elements in accordance with D1.1) Tier 2 – AISC Certification Program for Bridge and Highway Metal Comp onent Manufacturers (AISC 204) curr ent edition. The welder shall be AWS D1.1 certified. Tier 3 – The welder shall be AWS D1.1 certified.

541.3.5 5.1.2 Testing of Complete Penetration Welds

The Contractor shall conduct nondestructive QC radiographic tes ting on complete penetration welds in accordance with AWS D1.5 or D1.1 (as appli cable). Section 541: Steel Structures Page 496 The Department may allow ultrasonic testing as a substitute for radiography. The Contractor shall submit an ultrasonic testing Plan for approval at least 30 Days before the start of fabrication. The Contractor shall provide detailed informat ion about the Fabricator’s previous experience with ultrasonic testing and resumes showing the training and experience of persons performing the testing. The Contractor shall not us e ultrasonic testing for cases described in Section 6.7.1.1 o f the AASHTO/AWS D1.5-Bridge Weld ing Code.

541.3.5 5.2 Bolted Connections

The Contractor shall bolt with high strength bolts in accordanc e with Section 542, “High- Strength Bolts.” The Contractor shall make bolt holes 1/16 inch larger than the nominal diameter of the connector, unless otherwise specified.

541.3.5 5.3 Gaps between Ends of Abutting Members

Where the Contract requires abutting milled joints, the Contrac tor shall ensure there are no gaps. The Contractor shall face the ends to provide a full and even bearing when assembled. Where the Contract requires close joints, the Contractor shall not exceed 1/8 inch between the ends of abutting members. The Contractor shall not exceed 1/4 inch between abutting ends of girders at splices.

541.3.5 6 Camber Verification

The Contractor shall verify girder camber during the laydown op eration. Unless assembling girders in the horizontal position, the Contractor s hall meet the total camber dimensions less the deflections produced by the weight of the g irder.

541.3.6 Erection Requirements

The Contractor shall erect the Structure in accordance with AAS HTO/NSBA Steel Bridge Collaboration S10.1, Steel Bridge Erection Guide Specification . If requested by the Project Manager, a Pre-Erection Conference shall be held prior to start of erection. The agenda shall be the review of the erect ion Plan.

541.3.6 1 Placement of Bearings

The Contractor shall ensure that column bases and bearing devic es bear fully and uniformly on Substructures. The Contractor shall not place bea rings on pier or abutment Bridge seat areas that are improperly finished or irregular. T he Contractor shall grout to achieve uniform bearing only when the Contract allows grouting. The Contractor shall place masonry plates and beam and girder s pan pedestals on impregnated fabric pads approv ed by the Project Manager at leas t 1/8 inch thick.

541.3.6 2 Anchor Bolt Holes

The Contractor shall core drill anchor bolt holes in accordance with Table 541.3.6.2:1, “Required Nominal Anchor Bolt Hole Diameters.” Required Nominal Anchor Bolt Hole Diameters Bolt diameter (inch) Hole diameter (inch) 3/4 1-1/2 1 1-3/4 1-1/4 2 The Contractor shall set anchor bolts using non-shrink grout fr om the Department’s Approved Products List. The Cont ractor shall remove excess mor tar after the grout has set. The Contractor shall ensure that anchor bolt washers and nuts b ear evenly against the steel- bearing surface. The Contractor shall ensure anchor bolts at t he expansion ends of spans allow the free movement of the span.

541.3.6 3 Field Bolting

The Contractor shall install high strength bolts in accordance with Section 542, “High- Strength Bolts.” The Contractor shall block main structural members to the desir ed camber before torqueing the bolted splice connections. For skewed steel Bridges with diaphragms perpendicular to the l ongitudinal centerline, the Contractor shall finger tighten diaphragm attachment bolts before deck placement. The Contractor shall fully torque bol ts after the deck slab is in p lace. Following completion of the Superstructure and after priming, t he Contractor shall fill open holes in exterior beams and girders with button head bolts before Final Acceptance.

541.3.6 4 Field Welding

Field welding of permanent steel elements will not be permitted unless shown in the Plans, with the following exceptions: 1. Field welds shown in the Plans; 2. Splices for driven pile; 3. Sole plate to girder shoe plate; 4. Pedestrian rails; 5. Shear studs installed in the fi eld for construction means an d methods; or 6. As approved by the Project Manager.

541.3.6 4.1 Field Welding Submittal and Qualifications

The Contractor shall submit a welding procedure and the welder’ s certification for the welder performing the Work. The welder certification must be c onsistent with the welding procedure and the welding position required to perform the Work . Qualifications of the welders shall be consistent with Section 541.3.5.5.1.1, “Welder Qualifications.”

541.3.6 4.2 Field Welding Inspections

The Contractor shall provide a ce rtified AWS Welding Inspector. This Inspector shall review and approve the welding procedure and the welder qualifi cations. This Inspector shall provide testing and documentation in accordance with Section 54 1.3.1, “Applicable Codes and Section 541: Steel Structures Page 498 Documents.” Documentation shall be submitted to the Project Ma nager within Seven (7) Days of completion of the welding activity.

541.3.6 4.3 Field Installation of Shear Studs

Should the Contractor elect to install shear studs in the field , the Contractor shall field weld studs with automatic stud welding guns that shall be used to weld studs to girders. The operator shall be qualified per AWS D1.5 Subsection 7.7.4. The base metal where the stud is to be welded shall be ground to bright metal immediately prior to the weld being made. Manual welding will not be allowed except to make repairs. Rep airs shall be in accordance with AWS D1.5 Subsection 12.6 . Repair fillet size shall be a m inimum of 5/16 inch. Field welded studs shall be inspec ted in accordance with Sectio n 541.3.6.4.2, “Field Welding Inspections.”

541.3.6 5 Pilot and Driving Nuts

The Contractor shall use pilot and driving nuts in driving pins . The Contractor shall show details on the Working Drawings. The Contractor shall furnish one (1) pilot and one (1) driving nut for each size pin.

541.3.7 Reserved

541.3.8 Disposal of Steel Structu res, Reinforcing Steel, Steel Debris or Steel Waste

The Contractor shall not reuse salvaged steel items from exist ing Structures on NMDOT Projects unless directed otherwi se in the Plans. Salvaged stee l shall be disposed of by Contractor as approved by the Project Manager.

541.3.9 Quality Assurance Inspection Frequency

541.3.9 1 Steel Inspections

The following Quality Assurance Inspections shall be performed by the Quality Assurance Inspector (QAI). Unless otherwise noted, the Inspections shall take place in the fabrication shop. Tier 1 – Rolled steel beams – minimum of one (1) QA Inspections per P roject; Plate girders – minimum of three (3) QA Inspections per Project ; Diaphragms and cross frames – inc lude with the above inspection s; and Overhead sign structures – min imum of one (1) inspection per fa brication shop per year. Tier 2 – Metal Bridge barrier rails – 40% of welds by length; Diaphragms for concrete Bridges – visual inspection upon delive ry to site; and Steel bearing components – 40% of welds by length. Tier 3 – Drop inlets – visual ins pection upon delivery to site; Safety grates – visual ins pection upon delivery to site; Cattle & game guards – visual i nspection upon delivery to site; Pedestrian rails – visual inspec tion upon delivery to site; Gates – visual inspecti on upon delivery to site; Access panels – visual inspection upon delivery to site; and Miscellaneous steel – v isual inspection upon delivery to site. It is recommended that a QA Inspection be performed at or near the completion of Section 541: Steel Structures Page 499 erection; this is in additi on to those listed above.

541.3.9 2 Coating Inspections for Paint and Powder Coating

The following Quality Assurance Inspections shall be performed by the Quality Assurance Inspector (QAI). Unless otherwise noted, the Inspections shall take place in the fabrication shop. The Project Manager may w aive coating inspections. Tier 1 – Rolled steel beams – one (1) inspection concurrent with a st eel inspection; Plate girders – one (1) inspecti on concurrent with a steel insp ection; Diaphragms and cross frames – no requirement; and Overhead sign Structures – photos of coating process shall be p rovided to the QAI with QC traveler documentation, vis ual inspection upon delivery to s ite. Tier 2 – Metal Bridge barrier rails – t wo (2) shop inspections are re commended per Project; this may be waiv ed by the Project Manager; Diaphragms for concrete Bri dges – no requirement; and Steel bearing components – vis ual inspection upon delivery to s ite. Tier 3 – Drop inlets – visual ins pection upon delivery to site; Safety grates – visual ins pection upon delivery to site; Cattle & game guards – visual i nspection upon delivery to site; Pedestrian rails – visual inspec tion upon delivery to site; Gates – visual inspecti on upon delivery to site; Access panels – visual inspection upon delivery to site; and Miscellaneous steel – v isual inspection upon delivery to site. It is recommended that a QA inspection be performed at or near the completion of erection; this is in additi on to those listed above.

541.3.9 3 Galvanized Elements

Galvanized elements shall be visu ally inspected upon delivery t o the site by the Project Manager.

541.4 Method of Measurement

If structural members are specified by a nominal unit weight, t he Department will calculate weight based on the no minal weights and dimensions. When structural members are not designated by a nominal unit we ight, the Department will calculate weight using the unit weights listed in Table 54 1.4:1, “Metal Unit Weights for Measurement.” The Department will deduct the weight of copes, cuts, bevels, a nd open holes from the gross weight. The Department will not make deductions for bolt holes. Table 541.4:1 Metal Unit Weights For Measurement Material Unit weight (lb./ft 3) Steel 490 Cast iron 445 Bronze 536 The Department will pay the weight of fasteners as indicated o n the Accepted Working Drawings.

541.5 Basis of Payment

Pay Item Pay Unit Structural Steel for Concrete Bridges Pound Structural Steel for Steel Bridges Pound Structural Steel for Miscellaneous Structures Pound

541.5.1 Work Included in Payment

The following Work and items will be considered as included in the payment for the main items and will not be measured or paid for separately: 1. Submittals including re-submittals; 2. Nondestructive testing; 3. Protective coatings; 4. Additional weight of heavier sections provided solely for th e Contractor’s convenience; 5. All Incidentals necessary for the completion of the Work; 6. Weld Material weight; and 7. All QC/QA requirements. Section 542: High-Strength Bolts Page 501