AASHTO Steel Bridge Erection Guide Specification Apr. 2004 Draft

7/29/2019 AASHTO Steel Bridge Erection Guide Specification Apr. 2004 Draft

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AASHTO/NSBA Steel Bridge Collaboration

S10.1

Steel Bridge Erection Guide Specification

April 9, 2004

AASHTO/NSBA Steel Bridge CollaborationTask Group 10, Erection


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PREFACE

This document is a DRAFT standard developed by the AASHTO/NSBA Steel Bridge Collaboration. The

primary goal of the Collaboration is to achieve steel bridges of the highest quality and value through

standardization of the design, fabrication, and erection processes. Each standard represents the consensusof a diverse group of professionals

As consensus documents, the Collaboration standards represent the best approach to the processes they

cover. It is intended that Owners adopt and implement Collaboration standards in their entirety to

facilitate the achievement of standardization, but it is understood that local statutes or preferences may

prevent full adoption for some. In such cases Owners should adopt these documents with the exceptions

they feel are necessary.

This document establishes and defines the basic, minimum requirements for the transportation, handling

and erection of steel bridge components to ensure safe and accurate steel erection as well as quality and

value in the completed bridge structure.

Disclaimer

All data, specifications, suggested practices presented herein, are based on the best available information

and delineated in accordance with recognized professional engineering principles and practices, and are

published for general information only. Procedures and products, suggested or discussed, should not be

used without first securing competent advice respecting their suitability for any given application.

Publication of the material herein is not to be construed as a warranty on the part of the American

Association of State Highway and Transportation Officials (AASHTO) or the National Steel Bridge

Alliance (NSBA) - or that of any person named herein - that these data and suggested practices aresuitable for any general or particular use, or of freedom from infringement on any patent or patents.

Further, any use of these data or suggested practices can only be made with the understanding that

neither AASHTO nor NSBA makes any warranty of any kind respecting such use and the user assumes all

liability arising therefrom.


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Steel Bridge ErectionGuide Specification

Draft - April 9, 2004 page iAASHTO/NSBA Steel Bridge Collaboration

TABLE OF CONTENTS

PART ONE - SPECIFICATION

Definitions

Erector Qualifications

Erection Procedures

Transportation

Material Storage

Bearings and Anchorages

Assembly

Field Bolted Connections

Field Welded Connections

Inspection

Repair

Appendices

PART TWO - COMMENTARY

PART THREE - SAMPLE PROCEDURES & CALCULATIONS

EP-1 Single Span Straight Steel Girder - to be developed

EP-2 Multi Span Straight Steel Girder - to be developed

EP-3 Multi Span Horizontally Curved Steel Girder - to be developed

CALC-1 Calculation for Girder Stability - to be developed

CALC-2 Calculation for Temporary Support - to be developed

PART FOUR - SAMPLE CHECKLISTS

CL-1 Erection Procedure Checklist

CL-2 Pre-Erection Field Checklist - to be developed


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Draft - April 9, 2004 page iiAASHTO/NSBA Steel Bridge Collaboration


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Draft - April 9, 2004 Page 1AASHTO/NSBA Steel Bridge Collaboration

1. Definition

Steel bridge erection is the process of transporting, handling and assembling steel bridge components in a

safe and efficient manner to result in a bridge structure that meets all the geometric and structural

requirements of the contract documents.

2. Erector Qualifications

Utilize an AISC Certified Steel Erector for all bridge construction which requires any of the following: a

single lift over ten (10) tons in weight, any one lift using two or more cranes/derricks/poles, spans over

water or active railroad/rapid transit tracks, erection from the water on floating equipment, phased

construction requiring lane closures combined with active lanes, curved girders, main member field

splices.

3. Erection Procedures

The Contractor shall submit a detailed erection procedure to the Owner for each bridge structural unit.

Prepare the procedure under the supervision of a qualified individual, experienced in steel erection. The

procedure shall address all requirements for erection of the structural steel into the final designed

configuration. The procedure shall satisfy all written Owner comments prior to the start of erection.

Include in the procedure, as a minimum, the following information:

a) Drawings

i) plan of the work area showing support structures (piers and abutments), roads, railroad tracks,

waterways, overhead and underground utilities and other information relative to erection.

ii) erection sequence for main members and secondary members (crossframes, diaphragms,

lateral bracing, etc.) noting any temporary support conditions, such as holding crane

positions, temporary supports, falsework, etc. Member shipping marks shall be the same as

used on shop detail drawings.

iii)bolted splice assembly requirements per Section 7 & 8


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iv) capacity chart for each crane configuration and boom length used in the work

v) center of gravity locations for main members

vi) detail, weight and arrangement of all rigging for main member picks

vii)lifting weight of each member

viii)location of each crane for each pick, showing radius, crane support (barges, mats, etc)

ix) main member delivery location and orientation

b) Calculations

i) design calculations indicating the load capacity and stability of temporary supports for

structure and crane

ii) calculations to substantiate structural integrity and stability of erected girders prior to

completion of bridge assembly

iii) calculations to provide capacity of Contractor fabricated rigging such as lift beams, spreader

beams, beam clamps, etc. Submit manufacturers' certification or catalog cuts for pre-

engineered devices

c) Coordination Items

i) review/approval by other agencies as required, eg, railroads, Coast Guard, etc.

ii) follow on construction activities which occur prior to completion of steel erection, such as

concrete deck pours.

4. Transportation

4.1 The Contractor is responsible for coordinating delivery from the fabricator to the jobsite and for

providing adequate site access.


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4.2 The Contractor is responsible to submit a shipping plan to the Owner indicating support and tie-

down points for main members during transportation to the job site.Ship main members upright,

unless otherwise approved by owner. Load, support, and unload main members in a manner that

will not damage, excessively stress, or deform the steel, nor subject it to repeated stress reversals.

4.3 Ship fasteners in sealed, watertight containers.

5. Material Storage

5.1 Place material to be stored on blocking above the ground. Properly drain the ground and keep

material clean. Store girders and beams upright and shored. Support all members to prevent

damage.

5.2 Store fasteners, welding consumables, and machine finished parts inside covered structures or

otherwise protected from the weather. Fasteners removed from storage should be installed by

the end of the work shift. Return unused fasteners to storage at the end of the work shift.

5.3 Store and handle welding consumables in accordance with the AASHTO/AWS D1.5 Bridge

Welding Code.

5.4 Report any damaged material to the Engineer.

6. Bearings and Anchorages

6.1 Document all substructure locations (lateral and longitudinal), existing anchor bolt locations,

bearing seat elevations, and other pertinent information in a Contractor survey, conducted prior

to start of erection. Provide the Owner with notification prior to this survey, so that he may

participate. Document and report to the Owner any discrepancies between the survey findings

and the Contract plans.

6.2 Place bearing devices on properly finished bridge seat bearing areas. Notify the Owner if seats

are out of level or at incorrect elevations, and determine corrective actions to be taken.


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6.3 When setting bearings, make corrections for ambient temperature and anticipated rotation due to

dead load deflection of the member attached to the bearing. Position bearings such that the first

position, including corrections for temperature and dead load rotation, is within manufacturers

specification. Notify the Owner if anchor bolt locations do not permit proper positioning, and

determine corrective actions to be taken.

6.4 In addition to the dimensional tolerances in AWS D1.5 for steel bearing contact areas, members

shall seat on bearing devices with no final gaps exceeding 1/16.

7. Assembly

7.1 Erect and assemble all members in accordance with the procedures satisfying Section 3. The

proposed crane location(s) and member delivery location(s) may require modification in the field

to suit changing jobsite conditions. However, cranes and material to be lifted must be located

such that the lift is safe and within the crane's certified capacity for all required positions.

7.2 Curved girders and long span straight girders shall be stabilized with falsework, temporary

bracing, or holding cranes until a sufficient number of adjacent girders are erected with

diaphragms and crossframes connected to provide the necessary lateral stability.

7.3 All trusses shall be erected on falsework unless approved by the Owner. When erecting trusses,

the falsework shall remain in place until all connections are completed.

7.4 Falsework and temporary supports shall be detailed in a manner to insure that the temporary

elevation of supported steel accommodates the deflections that will occur as the structure is

completed.

7.5 Drift pins will normally be required to align holes for field splices. Field reaming will only be

allowed to facilitate fit-up with the Owner's prior approval. Any abnormal distortion of the

member or damage to the holes during the alignment process shall be immediately reported to

the Owner.


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7.6 For splice connections of main members, as well as diaphragm or cross-frame connections for

curved girders; fill at least 50% of the holes with erection bolts in a snug tight condition or full

size erection pins, with at least half (25% of all holes) being bolts, prior torelease. Uniformlydistribute the filled holes throughout the connection, except install pins at or near the corners of

main member connections. Permanent bolts may be used as erection bolts, provided they are

installed in accordance with Section 8.4. For complex structures (arches, trusses, etc.), fill holes

in accordance with erection procedures.

7.7 Any abnormal member deformation or brace deflection after crane release shall be immediately

reported to the Owner

8. Field Bolted Connections

8.1 Use bolts meeting the requirements of ASTM A325, ASTM A490, or ASTM F1852

8.2 Fully tension all bolts in the completed bridge prior to completion of steel erection, unless

otherwise noted.

8.3 No loose mill scale, dirt, or other foreign material that would preclude solid seating of the parts

is allowed on faying surfaces of bolted connections.

8.4 Verify bolt installation method prior to bolt installation, in accordance with Section 7 of the

RCSC Bolt Specification for Structural Connections Using ASTM A325 of A490 Bolts, dated

June 23, 2000 (referred hereafter as the Bolt Specification and currently available at

http://www.boltcouncil.org/download RCSC Specification.htm ). Additionally, perform fastener

assembly Rotational Capacity test per Appendix 1 or 1A.

8.5 Install and tighten bolts using any of the methods allowed per the Bolt Specification, paragraph

8.2. Tighten bolts to the minimum tension shown in the Bolt Specification,Table 8.1. Fully

tension bolts before exposure to the elements affects their torque characteristics.


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9. Field Welded Connections

9.1 Field welding and nondestructive testing shall be performed according to the current

AASHTO/AWS D1.5, Bridge Welding Code or other code (s) as specified in the contract

documents. Field welding is not allowed unless shown on the plans or approved by the

Engineer.

9.2 All structural field welding shall be done by the Shielded Metal Arc Welding (SMAW) process.

Flux Cored Arc Welding (FCAW) and Submerged Arc Welding (SAW) may also be allowed for

field welding when approved by the Engineer. Gas Metal Arc Welding (GMAW) and other gas

shielded welding processes are prohibited.

9.3 Qualification

9.3.aWelder Qualification. Test welders according to Section 5, Part B of AWS D1.5 in the

same position required for field welding as determined by the Engineer. Field Welder

qualification shall remain in effect indefinitely unless the welder is not engaged in welding

for a period of three months or more, or unless there is some specific reason to question the

welder's ability.

9.3.b Procedure Qualification. No field welding shall be performed until acceptable welding

procedures have been written and established by test. The weld procedure tests shall be

done in the same position and joint configuration required for the field welding (e.g., 3F and

4F for fillet welding and 3G and 4G for groove welding). The written welding procedures

shall be qualified after testing of the welds is completed. These tests shall be according to

Section 5 of AWS D1.5 or as specified in the Contract Special Provisions. Tests shall be

performed on steel plate material the same type as that to be welded, with mill certification

provided.

9.4 Welding Requirements


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9.4.aMake available a written copy of the approved welding procedure to the field welders.

9.4.bThe contact surfaces and joints to be field welded and the surrounding area shall be blast

cleaned or ground prior to welding. Loose mill scale, coatings, galvanizing, grease, oil, rust,

moisture, or other contaminates shall be removed from the base metal prior to welding.

Joints to be field welded shall be ground to remove pitting and irregularities. Joints to be

welded shall be prepared and any foreign material removed according to Section 3 of AWS

D1.5.

9.4.cThe parts to be joined shall be brought into as close contact as practicable according to

Section 3.3.2.1 of AWS D1.5.

9.4.dField welding shall not be allowed when the ambient air temperature is below 0o F or

during periods of precipitation unless the area to be welded is heated and housed in a

manner approved by the Engineer. See Section 3.1.3 of AWS D1.5.

9.4.eElectrodes shall be purchased in hermetically sealed containers and/or dried in an oven

according Section 4.5.2 of AWS D1.5. Electrodes shall be redried no more than one time.

Electrodes that have been wet shall not be used.

9.4.f All surfaces to be welded shall be preheated 3 inches in all directions from the weld.

Minimum preheat shall be 250o F for plate thicknesses less than or equal to 11/2 inches,

300oF for plate thickness exceeding 11/2 inches up to 21/2 inches and 350oF for plate

thicknesses over 21/2 inches. Preheating methods shall not cause damage to adjacent

coated surfaces, neoprene bearings and other heat sensitive components.

10.Inspection

10.1The alignment, profile and fastening of the erected steel shall be subject to inspection by the

Owner.

10.1.aTolerances

10.1.a.1 Deviation from theoretical horizontal alignment shall not exceed the following:


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+- 1/8 inch x (total length, in feet, between supports)/10

Deviation shall be measured at the top and bottom flanges, with the larger deviation

being the control. If the top and bottom flanges are on opposite sides of the

theoretical horizontal alignment, the total deviation (top flange plus bottom flange)

shall not exceed the value computed above. Theoretical horizontal alignment is to

be provided by the Engineer and calculated under steel dead load conditions only.

10.1.a.2 Deviation from theoretical erected web position

+- 3/32 inch x (web depth, in feet)

Deviation is the horizontal displacement between the top and bottom of the web.

Required theoretical erected web position is to be provided by the Engineer and

calculated under steel dead load conditions only.

10.1.a.3 Deviation from theoretical vertical alignment

- 0, + 1/4 inch x (total length, in feet, from nearest support)/10

Deviation shall not exceed 3 /4 in cantilever sections or 1 1/2 between supports.

Theoretical vertical alignment is to be provided by the Engineer and calculated

under steel dead load conditions only.

10.2 It is the Contractors responsibility to survey steel profile and alignment during and after

completion of steel erection, with verification by the Owner.

10.3 Bolt tension shall conform to the requirements of the Bolt Specification.

10.4 Visual inspection and nondestructive testing shall be performed on 100 percent of all field

welds. Welds shall be accepted according to Section 3.6 and 6.26 of AWS D1.5.

10.4.a Welds shall be free of rust, scale, coatings, and other foreign material prior to conducting

nondestructive testing (NDT). NDT shall include liquid dye penetrant (PT), magnetic

particle testing (MT), ultrasonic testing (UT) or radiograph testing (RT). Liquid dye

penetrant or magnetic particle testing shall be used for all fillet and partial penetration butt


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welds. Ultrasonic testing or radiograph testing shall be used for all complete penetration

butt welds, plug welds and slot welds.

10.4.bNondestructive testing methods shall be according to AWS D1.5. The Engineer shall

determine the frequency, location and type of NDT performed by the Contractor prior to

accepting the work. Personnel qualified as NDT Level II or Level III according to the

American Society for Nondestructive Testing (ASNT), Recommended Practice No. SNT-

TC-1A shall perform all tests. The NDT personnel shall provide proper certifications to

the Engineer prior to doing the work. The Engineer shall witness all nondestructive

testing. Welds that are cracked or determined to be unacceptable by the Engineer shall be

rejected and repaired at the Contractor's expense.

10.5 Inspect and test repaired welds in accordance with Section10.

11.Repair

11.1 The Contractor is responsible for documenting damage and proposing the method of repair and

submitting same to Owner.

11.2 Correct misaligned steel so that alignment tolerances specified in the Contract Documents are

achieved. The Contractor is responsible for proposing the method of realignmentand

submitting same to Owner for approval.

11.3 Submit repair procedures for damaged or misaligned steel in the form of sketches and/or

written procedures as applicable. Submit information in sufficient detail for the Owner to

adequately review the repair application.

11.4 Repair welds in accordance with Section 3.7 of AWS D1.5.


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Appendix 1

ROTATIONAL CAPACITY TEST

(Long Bolts in Tension Calibrator)

per FHWA Report No. FHWA-SA-91-031, dated May 1991, Appendix A1

Procedure for Performing Rotational Capacity Test, Long Bolts in Tension Calibrator

EQUIPMENT REQUIRED:

1. Calibrated bolt tension measuring device of size required for bolts to be tested. Mark off a vertical lineand line 1/3 of a turn, 120 degrees; and 2/3 of a turn, 240 degrees, from vertical in a clockwise direction

on the face plate of the calibrator.

2. Calibrated torque wrench.

3. Spacers and/or washers with hole size no larger than 1/16 in. greater than bolt to be tested.

4. Steel section to mount calibrator. Flange of girder or cross frame accessible from the ground issatisfactory.

PROCEDURE:

1. Install nut on bolt and measure stick out of bolt when 3 to 5 full threads of the bolt are located betweenthe bearing face of the nut and bolt head. Measure the bolt length, the distance from the end of the

threaded shank to the underside of the bolt head.

2. Install the bolt into the tension calibrator and install the required number of shim plates and/or washer(one washer under the nut must always be used) to produce the thread stickout measure in Step 1.

3. Tighten bolt using a hand wrench to the snug tensions listed below 0 kips, +2 kips

Bolt Dia. (in.) 1/2 5/8 3/4 7/8 1 1-1/8 1-1/4 1-3/8 1-1/2Snug Tension (kips) 1 2 3 4 5 6 7 9 10

4. Match mark the nut to the vertical stripe on the face plate of the bolt calibrator.

5. Using the calibrated manual torque wrench, tighten the bolt to at least the tension listed below andrecord the torque required to reach the tension and the value of the bolt tension. Torque must be

measured with the nut in motion.

Bolt Dia. (in.) 1/2 5/8 3/4 7/8 1 1-1/8 1-1/4 1-3/8 1-1/2Tension (kips) 12 19 28 39 51 56 71 85 103


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6. Further tighten the bolt to the rotation listed below. The rotation is measured from the initial markingin Step 4. Record the bolt tension. Assemblies which fail prior to this rotation either by stripping or

fracture fail the test.

Bolt Length

(measured in Step 1)

4 x bolt dia. or less Greater than 4 but no

more than 8 x bolt dia.

Greater than 8 x bolt

dia.Required Rotation 2/3 1 1-1/3

7. The bolt tension measured in Step 6 after the required rotation must equal or exceed the values in thetable shown below. Assemblies which do not meet this tension have failed the test.

Bolt Dia. (in.) 1/2 5/8 3/4 7/8 1 1-1/8 1-1/4 1-3/8 1-1/2Tension (kips) 14 22 32 45 59 64 82 98 118

8. Loosen and remove nut, and examine the threads on the nut and bolt. No signs of thread shear failure,stripping, or torsional failure of the bolt should be evident. Assemblies which have evidence of

stripping have failed the test.

9. Calculate and record the value of 0.25x the tension (pounds = kips x 1000) measured in Step 5 x thebolt diameter in feet. The torque measured and recorded in Step 5 must be equal to or less than this

calculated value. Assemblies with torque values exceeding this calculated value failed the test.


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Appendix 1A

ROTATIONAL CAPACITY TEST

(Bolts Too Short to Fit In Tension Calibrator)

per FHWA Report No. FHWA-SA-91-031, dated May 1991, Appendix A1

Procedure for Performing Rotational Capacity Test, Bolts Too Short to Fit Tension Calibrator

EQUIPMENT REQUIRED:

1. Calibrated torque wrench and a spud wrench or equivalent

2. Spacers and/or washers with hole size no larger than 1/16 in. greater than bolt to be tested.

3. Steel section with normal size hole to install bolt. Any available splice hole can be used with a platethickness that will provide the number of threads under the nut required in Step 1 below. Mark off a

vertical hole and lines 1/3 of a turn, 120 degrees; 1/2 of a turn, 180 degrees; and 2/3 of a turn, 240

degrees, from vertical in a clockwise direction on the plate.

PROCEDURE:

1. Install nut on bolt and measure stick out of bolt when 3 to 5 full threads of the bolt are located betweenthe bearing face of the nut and bolt head. Measure the bolt length, the distance from the end of the

threaded shank to the underside of the bolt head.

2. Install the bolt into the hole and install the required number of shim plates and/or washer (one washerunder the nut must always be used) to produce the thread stickout measure in Step 1.

3. Snug the bolt using a hand wrench. The snug condition should be the normal effort applied to a 12 inchlong wrench. The applies torque should not exceed 20% of the torque determined in Step 5.

4. Match mark the nut to the vertical stripe on the plate.

5. Tighten the bolt by turning the nut using the torque wrench to the rotation listed below. A secondwrench must be used to prevent rotation of the bolt head during tightening. Record the torque to reach

this rotation. Torque must be measured with the nut in motion.

Bolt Length





dia.

Required Rotation 1/3 1/2 2/3

The measured torque should not exceed the values listed below. Assemblies which exceed the listed

torque have failed the test.

Bolt Dia. (in.) 1/2 5/8 3/4 7/8 1 1-1/8 1-1/4 1-3/8 1-1/2Torque (ft-lbs) 150 290 500 820 1230 1500 1500 2810 3690


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6. Tighten the bolt further to the rotation listed below. The rotation is measured from the initial markingin Step 4. Assemblies which fail prior to this rotation either by stripping or fracture fail the test.

Bolt Length





dia.Required Rotation 2/3 1 1-1/3

7. Loosen and remove nut, and examine the threads on the nut and bolt. No signs of thread shear failure,stripping, or torsional failure of the bolt should be evident. Assemblies which have evidence of

stripping have failed the test.


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COMMENTARY

3. A qualified individual is one who, by possession of a recognized degree, certificate of professional

standing, or who by extensive knowledge, training and experience, has successfully demonstrated the

ability to solve or resolve problems related to steel bridge erection. The Owner may require that the

individual preparing the erection procedure be a licensed Professional Engineer. Complex structures

(tied arch, moveable truss) should have specific erection requirements noted in the Contract. The

erection procedure should be submitted as soon as possible after contract award. The erector is

encouraged to attend a prebid and preconstruction meeting. Projects that involve complex erection or

multi-agency review can be expected to require additional time for review of submitted erection

procedure.

3.a.i Other parameters may also need to be shown on the plan of the work area, such as Right of Way.

3.a.viii For operations on navigable waterways, the configuration of the barge(s), loading sequence, stability

provisions (tie downs, piles, etc) and calculations, safety measures (emergency boat, notification plans),

coordination plan for regulatory agencies and other water traffic, and the details and anticipated

schedules of obstructing the navigable channel should be required.

3.b Design criteria to be established or approved by the Owner.

3.b.ii Complex erection projects may require input from the structural designer in addition to the original

design calculations such that the contractor can confirm constructability of the structure during various

erection stages. The Owner should ensure that the structural designer is available to consult with the

Contractor in these cases.

3.c The Contractor should coordinate activities with the Owner/Engineer, Fabricator, and Erector. Special

coordination requirements may be included in the Contract. Examples would be Corp of Engineers,


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Railroads, Coast Guard, maintenance and protection of traffic control, school bus routes, and

emergency vehicle routes.

4.2 Care should be exercised to avoid coatings damage from slings, chokers, clamps, etc. Also, limiting the

length of members overhanging the rear wheels of a trailer may reduce the range of stress reversals and

potential damage from ground strikes.

6.1 Bearing seat elevations must allow for sufficient clearance under bearings for proper installation of

grouting

7. Jobsite conditions vary on a daily basis and are often not as they were anticipated to be when the

erection procedure was conceived and submitted to the owner. Consequently, the need to deviate from

the submitted erection procedure may arise during the course of a bridge project. It is the Contractors

responsibility to erect the steel in a safe and efficient manner. The Owner's review and disposition of

erection procedure changes to suit jobsite conditions should be handled in an expeditious fashion and

avoid delaying the work.

7.5 Examples of an abnormal hole would be one that is non-cylindrical, not perpendicular to the faying

surface, or out of round by more than 1/16".

8.4 It is required that connections be brought to the snug condition prior to fully tensioning bolts. It may be

difficult to achieve the snug tight condition for large main member connections, which utilize many

bolts and/or plies of thick material. The engineer may require a minimum of ten percent of each

connection be filled with fully tensioned temporary bolts prior to installing permanent bolts. Permanent

bolts can then be installed in the remaining holes in accordance with the Bolt Specification. Finally,

remove the temporary bolts and install permanent bolts at each location of temporary bolts.

9.1 Specific parts of AWS D1.5 have been referenced in this section as opposed to the entire code. AWS

D1.5 was written mostly for the use of shop fabricating structural steel members. Field welding


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structural steel members presents environmental and geometric conditions that exceed those in the shop.

Rain, humidity, and wind are examples of conditions that can not be controlled in the field but can be

controlled in the shop. Difficultly in steel fit-up, access to the joint by the welder and welding position

are geometric constraints that can adversely affect the quality of the weld. The owner must specify in

the contract documents what welding code is to be used. Codes other than AWS D1.5 will not have the

same referred sections as that of AWS D1.5 and sections specified herein. The owner must coordinate

code sections other than AWS D1.5 with sections in these documents.

9.2 It is recommended that E7018 or E7016 electrodes be used for field welding. These are low hydrogen

electrodes and produce good quality welds when stored according to Section 4.5.2 of AWS D1.5. Flux

Core Arc Welding (FCAW) may be used without gas shielding. Submerged Arc Welding (SAW) can

be used providing it is used exclusively for welding butt welds in the flat position and fillet welding in

the flat and horizontal position. When wind speeds exceed 20 mph, the granular flux required for

SAW may blow away if precautions are not taken to block strong winds. Welding with gas shielding

processes have been prohibited because of potential loss of shielding gases by drafts from nearby

moving objects or when wind speeds exceed 5 mph.

9.3 Unlike shop welding, workers welding in the field for contractors move from project to project and

keeping track of welders that are qualified can be difficult. It is recommend that field welders be

qualified according to Section 5 of AWS D1.5 in the position, using the process, and material (grade of

steel) to be used in the production welding. It is also recommended that field welders qualify

indefinitely unless the welder is not engaged in welding for a period of three months, or unless there is

some reason to question the welders ability. Many times field welders are labors, iron workers,

carpenters, machinist, foremen, etc. These contractor employees will move from project to project and

from company to company. Keeping track of who is qualified and who is not can be a difficult task.

Therefore, it is recommended that an inventory of qualified field welders be kept so that project

personnel can keep track of which contractor personnel are qualified to do field welding. Therefore, a


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work record or database of qualified field welders should be maintained by the owner. A frequency as

short as two years between each qualification test for each welder may be used if tracking of both

welders (project to project and company to company moves) and proper documentation of qualified

welders becomes clumsy or difficult to maintain.

9.3.b Parameters (amperage, volts, travel speed, etc.) used by the welder for qualification and/or joint

configuration mock-up (if necessary) should be used to write the Welding Procedure Specification

(WPS). AWS D1.5, Annex III-2 Sample Welding Procedure Specification form can be used to write

the WPS.

9.4.cWhen the ambient air temperature is below 0o F or during periods of precipitation when environmental

conditions meet the requirements of Section 3.1.3 of AWS D1.5 and/or the welders ability to make

sound welds are a concern, heating and housing should be used. See AWS D1.5 Commentary C3.1.3

for a detail explanation of cause and effect of weld quality due to ambient air temperature, moisture or

precipitation, and wind speed.

9.4.d It is required that electrodes be keep dry at all times. Electrodes will absorb moisture if not properly

stored according to the requirements of AWS D1.5. If electrodes are not stored according to the

requirements of AWS D1.5 they will absorb moisture and produce poor quality welds during

production welding. Electrode drying ovens should be at the project site located near the welders

work station at all times. Once the electrode container is opened, electrodes should be place in the

ovens and stored at temperatures according to AWS D1.5.

9.4.ePreheating the weld joint just prior to welding is extremely important in the field to achieve high

quality welds. NCHRP Report 321 provides recommended preheats for field welding applications.

These are the preheats used in most field welding applications. These elevated preheats (as compared

to those required for shop welding) provide the following advantages for good sound weld quality:

dries out the surface removing moisture, expands the base metal reducing residual stresses, diffuses


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hydrogen preventing cracking in the weld metal, slows the cooling rate, and permits gases to escape

preventing porosity.

10.1.a.2 The location the measurement for deviation from theoretical web position will vary depending on

bridge type. For straight or skewed girders, measure adjacent to bearing stiffeners. For curved

girders, measure adjacent to bearing stiffeners and also at midspan. For other bridge types,

measurement locations are to be provided by the Engineer.

10.1.a.3 Tolerance in the negative direction, i.e. vertical alignment lower than theoretical, has not been

permitted to ensure that the distance between top of flange and top of deck can be maintained,

thereby avoiding thickening the haunch (or deck) to suit. Installed location lower than theoretical

may be acceptable upon review by the Engineer. For a typical girder bridge, some agencies may

choose to control only the elevation of the girder splices and accept vertical alignment between

splices (within the tolerance on shop camber). Also note, some of the tolerance on vertical alignment

may be 'consumed' by the tolerance on shop camber of the fabricated girder.

10.4 All field welding should be inspected visually by a Certified Welding Inspector (CWI). In addition,

field welds should be evaluated non-destructively by personnel qualified as NDT Level II or III

according to the American Society for Nondestructive Testing (ASNT), Recommended Practice No.

SNT-TC-1A. The NDT personnel should provide proper certifications to the Engineer prior to doing

the work. Welds should be cleaned prior to conducting nondestructive testing (NDT). The Engineer

should determine the frequency, location and type of NDT performed by the Contractor prior to

accepting the work. NDT includes liquid dye penetrant (PT), magnetic particle testing (MT),

ultrasonic testing (UT) or radiograph testing (RT). PT or MT is used for fillet and partial penetration

butt welds. UT or RT is used for complete penetration welds, plug welds and slot welds.


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AASHTO / NSBA STEEL BRIDGE COLLABORATION

ERECTION PROCEDURE CHECKLIST

PART 1 ERECTION PROCEDURE DRAWING

PLAN: To scale plan of work area showing supporting structures, roads, railroads, waterways, overhead &underground utilities, adjacent structures, etc.; and framing plan with member shipping marks and indicate field splice locations if applicable

Location of temporary supports, falsework, holding cranes

Location of crane positions on plan showing pick radii

Elevation view of crane and member Included Not ApplicableCrane Support Method: barges, mats Included Not Applicable

Member delivery location and orientation

DETAILS: Detail and arrangement of member rigging: show sizes, capacities, and location of center of gravityof each pick

Falsework and temporary support details: show sizes and capacities

Crane capacity chart indicating crane type, lifting capacity at given radius and orientation,counterweight requirements, and boom length

Pick weight chart indicating weight of member, plus rigging and any attachments

Written procedure indicating erection sequence for main and secondary members (crossframes,diaphragms, lateral bracing, etc.), including the following: method of tie down of individual pieces,time and method of connections of diaphragms and lateral bracing and field splices;

PART 2 CALCULATIONS

Calculations for load capacity and stability of temporary supports for structure: falsework, tie downs,lifting beams, spreader beams, etc.

Calculations indicating capacity of temporary crane supports: Included Not Applicable

Calculations to substantiate structural integrity and stability of members prior to completion of bridgeassembly

Calculations indicating structural integrity of any partially bolted main splice after release of externalsupport system

Calculations to substantiate structural integrity of abutments and retaining walls affected bysurcharge from crane

PART 3 ASSOCIATED DATA

Manufacturers cut sheets for rigging devices: beam clamps, slings, wire rope, shackles,turnbuckles, chains, straps, etc., and pre-engineered falsework, if applicable

Statement as to status of coordination with parallel entities requiring review: railroads, Coast Guard,

Corps. Of Engineers, etc.

PROJECT DESCRIPTION __________________________________________________________________________

COMPLETED BY _________________________________________________________________________________