2402Steel Bridge Construction

2402.1DESCRIPTION

This Work consists of the erection of those portions of Bridges and Structures that are made of structural steel and miscellaneous metals.

2402.2MATERIALS

2402.3CONSTRUCTION REQUIREMENTS

A General A.3 Assembly Assemble Bridge components in accordance with the match markings and erection P lans using procedures outlined in the Contract. If the Contract does not specify assembly procedures, assemble in accordance with recognized practices. B Handling and Storage of Materials B.1 Structural Steel Store girders and beams in an upright position. Keep Materials clean, dry, and in a properly drained area. Cover and shelter members that will be stored for greater than 3 months and provide for air circulation around the members. B.2 High Strength Fasteners Fasteners include, but are not limited to, bolts, nuts, washers, and direct tension indicator (DTI) washers. Before fasteners are delivered to the Bridge site, provide documentation of rotational capacity (ROCAP) testing in accordance with ASTM F3125, Standard Specification for High Strength Structural Bolts and Assemblies, Steel and Alloy Steel, Heat Treated, Annex A2, Rotational Capacity Test. The fasteners must be received in packages that match the fastener assembly combination as tested. If documentation of ROCAP testing is not received; then perform this testing in the field prior to installation. Store fasteners in sealed, waterproof containers. Locate the containers in an enclosed Structure that is protected from the elements. Submit a fastener storage Plan to the Engineer at least 14 Calendar Days prior to delivery of fasteners to the jobsite. In the Plan identify where fasteners will be stored, how fastener condition will be quality controlled, and what measures will be used to prevent corrosion. Notify the Engineer when shipments of fasteners arrive on the jobsite. For any Work shift, remove from storage only the number of fasteners required for that shift. At the end of the Work day, return fasteners not installed to storage as defined above. Prior to installation, ensure that the fastener condition has not changed due to weathering, mixture of tested assembly lots, or other reasons. In the event that changes have occurred, the Engineer will require re-qualification using ROCAP testing in the field for a minimum of three fastener assemblies of each combination to be used in permanent bolting.

C Straightening Bent Materials Straighten plates, angles, and other shapes using methods that will not fracture or damage the metal. Do not heat the metal unless allowed by the Engineer, in conjunction with the Structural Metals Engineer. If allowed and before performing any straightening operations, submit a straightening procedure to the Engineer for review and approval by the Structural Metals Engineer . Do not heat metal to temperatures greater than 1,200°F. After heating and straightening, allow the metal to slowly cool before inspecting for evidence of fracture or other damage. Repair galvanized and metallized coating in accordance with 2471, “Structural Metals.” D Temporary Works All Plans, Specifications, and calculations submitted under the provisions of this section must be prepared by a Professional Engineer, checked by a second Professional Engineer for completeness and accuracy, and certified by one of the aforementioned Professional Engineers licensed in the State of Minnesota. D.1 Falsework At least 42 Calendar Days before starting construction of the structural steel erection falsework, provide the Engineer with three copies of the detailed Plans and Specifications and two copies of the associated calculations for the proposed system to construct the falsework. Design the falsework to meet the requirements of AASHTO Guide Design Specifications for Bridge Temporary Works and AASHTO Standard Specifications for Highway Bridges. Ensure the documents include details to allow the construction of the proposed system by reference to the Plans and Specifications only. Provide calculations to verify the adequacy of any adjacent Structures that will be affected by surcharges from proposed falsework. D.1.a Falsework Plans Provide the following in the falsework Plans, as a minimum:

bracing

specified in the Plan

geometry D.1.b Timber Provide timber meeting the following requirements for falsework piles or members;

Provide straight steel members of adequate strength for the intended use. D.1.c Use of Falsework Do not erect the structural steel until meeting the following requirements:

requirements

Specifications has inspected the falsework after erection and has provided written certification to the Engineer stating the as- constructed falsework is approved for use

centerline of bearing for girder supports on falsework D.2 Formwork Except for attachment of screed rail support pipes, do not weld on primary stress-carrying members of the Bridge structure to fasten appurtenances not shown on the Plans or on the approved detail drawings. The Contractor may weld screed rail support pipes to the top flange with 1/4 inch longitudinal fillet welds no greater than 2 inches long. Do not weld in the negative moment area, as shown on the Plans as “Area A,” of the top flange of primary stress-carrying members of the Bridge Structure. Prepare the base metal and weld during ambient weather conditions in accordance with 2471.3G, “Structural Welding.” E Erection Provide a bolting Plan in accordance with 2402.3G.2.c, “Installation” for all structural steel erection. E.1 Analysis and Plans If the Plans show active public access (vehicular, railroad, trails, navigable waters, etc.) beneath the Structure before the complete erection of the beams and transverse members (e.g. diaphragms, cross-frames, lateral bracing) in a span, submit an erection Plan, Specifications, and calculations to the Engineer detailing the temporary works required to maintain structural adequacy and stability of the Bridge system for each step of the erection Plan. Perform design in accordance with AASHTO LRFD Bridge Design Specifications, AASHTO LRFD Bridge Construction Specifications, and AASHTO Guide Design Specifications for Bridge Temporary Works. All Plans, Specifications, and calculations must be prepared and certified by the Contractor’s Erection Engineer. The Contractor’s Erection Engineer must be a Professional Engineer licensed in the State of Minnesota. All documents included in the submittal must be checked by a second Professional Engineer for completeness and accuracy. Use struts, bracing, tie cables, and other devices used for temporary restraint of a size and strength capable of withstanding the stresses developed. Erect and brace at least two adjacent beams or girders, including transverse members, in any one span before suspending operations for the day. Adjust falsework to the “as-fabricated” geometry, which takes into account the shop blocking and any vertical tolerances used in the fabrication assembly. Maintain the falsework in place until the Erection Engineer approves the release of falsework supports. Remove falsework in accordance with 2401, “Concrete Bridge Construction.”

E.1.a Plan Requirements Provide the following in the erection Plans, as a minimum:

permanent connections of the transverse members to stabilize the beam

permanent connections of the girder splices if the requirements of 2402.3F.2, “Assembly,” will be modified E.1.b Calculation Requirements Provide the following in the erection calculations, as a minimum, for each stage of the proposed erection sequence:

permanent connections of the transverse members to stabilize the beam

impacted by surcharges due to cranes E.2 Preparation Refer to 2401.3F.3.b, “Bearing Seats,” for bearing seat tolerances and corrections. Any corrections must be completed prior to setting the bearing assemblies. Provide survey of X and Y coordinates and elevations at centerline of each bearing prior to setting the bearing assemblies. Immediately before assembly, remove temporary protective coatings from pins and pin holes, and clean the contact surfaces at connections of foreign matter. Clean the contact area between pins and bushings to bare metal for pin holes provided with bronze bushings before assembling. When required by the bearing supplier, make correction for temperature and rotation. Paint surfaces inaccessible after erection as required before fit-up.

F Field Fit-Up F.1 Stability and Safety Erect structural steel members in a manner that will provide safety to the workers, Inspectors, the public, and without damaging the steel members. Temporarily anchor, brace, and stabilize primary members, such as beams and girders, as erected to prevent sliding, tipping, buckling, or other movement, before placing transverse members. F.2 Assembly For the purposes of the Work specified in section 2402, “Steel Bridge Construction,” a primary member is defined as any member that carries the primary stresses of the S tructure. Beams and girders are primary members unless otherwise noted. When the Contract requires full assembly for fabrication, transverse members are also considered primary members. For purposes of this provision, bolt types are defined as follows:

tensioned per 2402.3G, “Connections.” These bolts are used to maintain both final geometry and strength of the connection throughout the service life of the Bridge.

in correct position during bolting operations in conjunction with erection pins . These bolts must be the same diameter as the permanent bolts.

installing erection pins and cannot be used in the permanent connection. Permanent bolts may be used as erection bolts when they remain in the as -manufactured condition and have not been previously tensioned as per Table 2402.3-1, “Bolt Tension.” Use erection washers with erection bolts. Do not use erection pins larger than the diameter of the hole or smaller than the hole diameter minus 0.030 inches. For connections with oversized holes, use pins or tapered spud wrenches to align the connection. Do not use any type of bolt to establish the alignment of the connection. Pins are considered effective for load transfer and geometry control, and erection bolts for maintaining tight steel. For the purposed of the Work specified in 2402, “Steel Bridge Construction,” snug tight is defined as the effort required to bring all plies of the connection together in firm contact. Snug bolts working from the interior of the connection to the free edges; this step will require a minimum of two passes over every bolt to ensure firm contact. The term “snug tight” is interchangeable with the field term of “tight steel.” Prior to beginning permanent bolting, use enough bolts tightened to a snug tight condition to bring all plies of the connection together in firm contact. Use the following pinning and bolting sequence on primary stress -carrying members, for establishing the “assembled connection:”

connection together during pin installation. Tension of installation bolts must not restrict alignment of the connection

connection. Balance the distribution of the pins throughout the connection.

With regard to load transfer, a portion of pins may be substituted with erection bolts under the following conditions:

Engineer demonstrating the connection forces during erection may be sustained by the proposed number of pins or be resisted in slip by prescribed number of tensioned erection bolts

satisfaction of the Engineer

for the purpose of geometry control

in the connection. Balance the distribution of the bolts throughout the connection. Tighten the erection bolts to a snug tight condition. Shipping bolts and installation bolts are not included in the erection bolt percentage requirement

Engineer, tension erection bolts necessary to sustain connection slip resistance. When live loads are carried during erection, use additional bolts and erection pins to compensate for the additional loads

Check bearing plates and assemblies for contact before placing the permanent connectors. Correct deviations from full bearing between parts, or between the B ridge seat and the bearing plates as approved by the Engineer. Readjust transverse members or splice plates, if required to correct deviations. For extreme deviations, the Engineer may direct re-cambering or other re-fabrication procedures. The Contractor may use properly shaped and sized fills or shims to correct minor deviations as approved by the Engineer. Make adjustments to erected sections to meet the following requirements at all support points (both permanent and temporary):

(total length along the girder, in feet, between supports)/10. Shift the spans if required to correct for alignment, skew, and proper anchorage and expansion device locations

1/4 inch x (total length, in feet, from the nearest support)/10. Modify camber and field splice plan elevations to account for as-built bearing seat elevation as necessary F.3 Permanent Bolting Permanent bolt girder splices prior to releasing girders from any type of temporary support (i.e. cranes, shoring towers, blocking, etc.) unless allowed by the Contractor’s Erection Engineer Plan prepared in accordance with 2402.3E, “Erection.” Permanent bolting of transverse members will vary during the erection of steel Structures. The timing of this Activity is affected by the Structure type, how it was fabricated, and the means and methods utilized during erection. Fabrication utilizes either “ line assembly” or “full assembly” practices to position, locate, and build structural bolted connections. The erection Plan must clearly define when permanent bolting can occur for each connection in the steel Structure.

Permanent bolting of the transverse members will be authorized after the Contractor meets the erection tolerances and has addressed all written comments by the Engineer. Proceed with permanent bolting as follows:

free edges, in a manner that will minimize relaxation of previously tightened bolts

individually. After removal of an erection pin or erection bolt, replace with a permanent connector and tension before continuing Where DTI’s are used, perform Quality Control on permanent bolt tensioning before presenting to the Engineer for final inspection. Perform permanent connector tensioning within 10 Calendar Days after initial installation as exposure to the elements affects their rotational capacity test characteristics. Remove and re-lubricate permanent connectors that have been installed for more tha n 10 Calendar Days or if exposure has affected the rotational capacity test characteristics of the assembly. Perform new ROCAP tests on each lot combination of re-lubricated bolt assemblies. F.3.a Line Assembly For the purpose of the Work specified in 2402.3F, “Field Fit-Up,” the Department defines “Line Assembly” as the method by which the Structure was fabricated building the Structure one girder line at a time. It identifies that the Structure has had the girder splices drilled with standard size holes in a “no load” condition. It also identifies that secondary transverse members are connected with oversize holes and have not been subject to preassembly. When the Contract requires Line Assembly, do not start permanent bolting of transverse members until:

bearing and girder field splices are completed on both lines in the adjacent span(s)

prior to permanent bolting. Permanent bolting of transverse members outside of the area defined for allowable bolting is not allowed until the completion of the next span

Figure 2402.3-1 Plan view showing framing fabricated in Line Assembly and erection requirements prior to permanent bolting (without temporary falsework)

F.3.b Full Assembly For the purpose of the Work specified in 2402.3F, Field Fit-Up,” the Department defines “Full Assembly” as the method by which the Structure was fabricated. It identifies that the Structure has had the girder splices and transverse members drilled with standard size holes in a “no load” assembled condition. Field erection practices are required to erect the steel in a manner consistent with how it was fabricated and not induce secondary stresses. When the Contract requires Full Assembly, do not start permanent bolting of transverse members until:

points of bearing, girders lines for the entire span are erected, and field splices are completed in the span(s) immediately adjac ent to the span in question

prior to permanent bolting without the use of shoring towers Figure 2402.3-2 Plan view showing framing fabricated in Full Assembly and erection requirements prior to Permanent Bolting (without temporary falsework)

F.3.c With Temporary Falsework (Shoring Towers) An exception to the requirements in 2402.3F.3.a, “Line Assembly,” and 2402.3F.3.b, “Full Assembly,” is allowed where shoring towers are used without interruption to correct alignment, camber, grade, and skew. Shoring towers that are fully supporting the members in the as-fabricated, no-load position allow permanent bolting before all girders in the span are erected. For this exception, permanent bolting may begin when both girder lines are supported at three support points and field splices are completed on both lines of the adjacent span(s). Temporary shoring is an eligible point of bearing for erection purposes. See Figure 2402.3-3 below for conceptual illustration of requirements prior to permanent bolting with the use of shoring towers. Figure 2402.3-3 Plan view showing framing fabricated in Full or Line Assembly and erection requirements prior to permanent bolting (with temporary falsework)

F.3.d Ground Splices The Engineer may allow permanent bolting of field splices in beams or girders on the ground before Full Assembly of adjacent spans, provided the beams to be spliced are positioned on firmly supported blocking that replicates the as-fabricated geometry. Pin ground spliced beams with at least 25 percent pins and 25 percent snug tight bolts and present to the Engineer before permanent bolting. Fully tension and inspect primary member connections that are made up on the ground before erection prior to any lifting operation. F.4 Pin Assemblies Before assembling pins, coat pins and pinholes, including pinholes with bronze bushings, with a “bridge grease” as listed on the APL. Draw pin nuts tight, except for pin nuts with cotter keys. Upset the exposed thread at the face of the nut by center punching to prevent back off. If tightening pin nuts with cotter keys ensure the cotter key can be freely inserted and the pin is free to turn without binding under the Lomas nut. F.5 Construction Elevations After all permanent connections have been tensioned and inspected in accordance with 2402.3G.2.d, “Inspection,” take elevations at top of beams under steel dead load only deflections. Take elevations at five foot increments along the centerline of the beam starting at each centerline of bearing and proceeding up station. Restart five foot increment at each centerline of bearing for continuous spans.

Allow for total dead load deflections as shown in the Plan to enable building forms to the correct grade and specified slab thickness. Provide a copy of the elevations to the Engineer. For long, multiple span, continuous Bridges, the Contractor may request in writing to take elevations prior to tensioning and inspection of all permanent connections . Provide the Engineer with the following items:

field section ends for each stage of the erection sequence

deliverables required G Connections Connections, including fill plates and shims, must be clean and undamaged so as not to impact the design slip criteria. Do not damage paint and maintain the appropriate thickness to meet compliance for the designed slip coefficient. Unless the Contract requires or the Engineer approves otherwise, provide field connections made with high strength bolts or pin bolts. G.1 Welded Connections Weld field connections in accordance with 2471, “Structural Metals.” G.2 Connections Using High Strength Bolts G.2.a General Install bolts with heads outward for the webs of fascia girders. Install bolts with heads downward for the flanges of beams and girders spanning H ighways, Streets, Roadways, and walkways. G.2.b Bolted Parts Ensure the slope of surfaces of bolted parts in contact with the bolt head and nut is no greater than 1:20 with respect to a plane normal to the bolt axis . Assemble bolted parts to fit solidly together. Do not separate bolted parts by gaskets or other interposed compressible Material. Assemble joint surfaces, including those adjacent to the bolt heads, nuts, or washers, free of the following:

Ensure contact surfaces of friction-type joints are free of coating Materials such as oil, galvanizing, and rust inhibitors. G.2.c Installation G.2.c(1) Bolt Tension Clean contaminants and corrosion from the threaded portions of bolts and nuts, before installing. Lubricate and dye nuts in accordance with 3391, “Fasteners.”

Tension each fastener to provide the minimum bolt tension shown in Table 2402.3-1 after bringing the connection to a snug-tight condition. Use the turn-of-nut or direct tension indicator method to verify bolt. As required by the Research Council on Structural Connection (RCSC), Specification for Structural Joints Using High-Strength Bolts, do not tension Grade A490 bolts or galvanized Grade A325 bolts more than one time. Uncoated Grade A325 bolts with free spinning nuts and no evidence of elongation may be tensioned up to two times with the Engineer’s approval. Ensure proper lubrication prior to tensioning. Discard and replace fractured or damaged bolts. If using impact wrenches, provide wrenches capable of performing the required tensioning of each bolt in 10 seconds. Provide the Engineer with a job-specific fastener installation Plan at least four weeks before the start of steel erection. The Plan will, at a minimum, include Pre-Installation Verification (PIV) testing per RCSC, identification of all tools and equipment, access requirements, specific information from erection plan (as required), and methods for bolt snug - tightening and permanent bolting PIV testing prior to permanent bolting is required to verify the following:

procedures

adequately

lubrication) are in suitable condition for proper bolting procedure and achieving needed results PIV testing requires the use of a bolt tension measurement device (i.e. Skidmore-Wilhelm). Ensure the measurement device has been calibrated within one year of the date of use. Perform PIV testing on at least three complete fastener assemblies of each combination of diameter, length, grade, and lot to be used in the Work. Perform PIV testing no earlier than 14 Calendar Days prior to permanent bolting. Submit PIV test results for each structure prior to the start of permanent bolting. For bolts that are too short to be calibrated using hydraulic load cell, calibrate using DTIs as the load cell. Once the DTIs have been calibrated, test the fastener assembly in a steel plate of similar thickness to that used in the permanent condition. Refer to the RCSC for more detail, except only one calibrated DTI needs to be used in the fastener assembly for each PIV test. Additional ROCAP or PIV tests are required whenever the condition of the fasteners or understanding of bolting crew is in question by the Engineer. Do not allow permanent bolting until the PIV test results and the fastener installation Plan are accepted by the Engineer in writing.

Table 2402.3-1 Bolt Tension Bolt Size, inch Minimum Tension*, kips Grade A325 Grade A490 3/4 28 35 7/8 39 49 1 51 64 1 1/8 64 80 1 1/4 82 102 * Equal to the values provided for ASTM F3125, Standard Specification for High Strength Structural Bolts and Assemblies, Bolts in RCSC Table 5.2, Minimum Bolt Pretension, Pretensioned and Slip- Critical Joints. G.2.c(2) Washers Provide fasteners with a hardened washer placed under the nut or bolt head being turned during tightening. Provide high strength bolts with a hardened washer under the bolt head and the nut if used in conjunction with full sized punched holes. If an outer face of the bolted parts has a slope greater than 1:20 with respect to a plane normal to the bolt axis, use a smooth beveled washer to compensate for the lack of parallelism. G.2.c(3) Direct Tension Indicator (DTI) Tightening When using DTIs to provide the minimum bolt tensions in Table 2402.3-1, install the indicators, including snug tight fit-up, as recommended by the manufacturer except for the following:

fastener if bolting through a short-slotted or oversized hole in accordance with 2471.3I.1.a, “Line Assembly”

hardened washer to separate the turned element from the DTI meeting the requirements of AASHTO LRFD Bridge Construction Specification 11.5.6.4.7

the requirements of ASTM F959, Standard Specification for Compressible-Washer-Type Direct Tension Indicators for Use with Structural Fasteners

except as modified in 2402.3G.2.d(3), “Inspection Procedure for Direct Tension Indicators (DTI)”

G.2.c(4) Turn-of-Nut Tightening Match mark all bolts after snug-tightening has been completed. Complete permanent bolting by turning the nut by the amount of rotation specified in this section. Progress with tightening systematically from the interior of the connection to the free edges. Do not rotate the part not turned by the wrench. For coarse thread heavy hexagon structural bolts and heavy hexagon semi-finished nuts, rotate nuts from snug tight condition in accordance with the following:

of beveled washers), rotate nuts 1/3 turn for bolt lengths no greater than 4 diameters, 1/2 turn for bolt lengths greater than 4 diameters to 8 diameters, and 2/3 turn for bolt lengths greater than 8 diameters to 12 diameters.

than 1:20 (beveled washers not used), rotate nuts 1/2 turn for bolt lengths no greater than 4 diameters, 2/3 turn for bolt lengths greater than 4 diameters to 8 diameters, and 5/6 turn for bolt lengths greater than 8 diameters to 12 diameters.

washers not used), rotate nuts 2/3 turn for bolt lengths no greater than 4 diameters, 5/6 turn for bolt diameters from 4 diameters to 8 diameters and, 1 turn for bolt lengths from 8 diameters to 12 diameters. Measure bolt length from the underside of head to extreme end of the bolt. Measure nut rotation as relative to bolt regardless of the element (nut or bolt) being turned. Rotate nuts within the allowable tolerance of 1/6 turn over and zero rotation under the rotation specified in list items (1), (2), and (3) above. G.2.c(5) Quality Management Provide a Quality Control Plan for Installation of fastener assemblies at least four weeks before the start of steel erection . Include the following items as a minimum:

assemblies

installed and when final tensioning occurred

readings

connection detail

Quality Manager staff will verify the fastener installation Plans were followed

G.2.d Inspection The Engineer will observe the installation and tightening of bolts to determine that the tightening procedure and bolt tensions comply with the requirements in this section. The Engineer will inspect the bolt tension in accordance with the following procedure unless otherwise specified: G.2.d(1) Calibration of Inspection Wrench Provide a manual inspection wrench calibrated in accordance with the following: Test each combination of bolt production lot, nut lot, and washer lot as an assembly. Test 3 assemblies per combination. Individually place bolts of the same grade, size, and condition, as the bolts under inspection in a calibration device (i.e. Skidmore Willhelm) capable of indicating bolt tension . Place a washer under the part turned in tightening each bolt. Provide test bolts in the same length as the bolts used in the Structure. Tighten each test bolt in the calibration device to an initial condition equal to 15 percent of the specified bolt tension and then to the minimum tension specified for its size in accordance with Table 2402.3-1. Apply the inspecting wrench to the tightened bolt and turn the nut or head 5 degrees, or 1 inch at 12 inch radius in the tightening direction. Measure the torque applied. Average the torque as measured in the tests of 3 bolts and use this “job-inspecting torque” in accordance with 2402.3G.2.d(3), “Inspection Procedure for Direct Tension Indicators (DTI).” Provide the inspection wrench and the bolt tension-indicating device as specified in this section. Allow the Engineer to witness the prescribed calibration tests. During calibration in accordance with 2402.3G.2.d(1), “Calibration of Inspection Wrench,” ensure the bolt and nut withstand rotation to two times the number of turns as specified in 2402.3G.2.c(4), “Turn-of-Nut Tightening,” without showing visible evidence of stripping the threads or failure of the bolt or nut. G.2.d(2) Inspection Procedure for Calibrated Wrench At the Engineer’ option, either the Engineer or the Contractor in the Engineer’s presence may operate the inspecting wrench as follows:

in the tightened direction, the inspecting wrench and its job-inspecting torque to a randomly selected 10 percent of the bolts or at least 2 bolts in each connection.

heads do not turn when applying the job-inspecting torque as indicated in item (1) above. If a nut or bolt head turns during the application of job-inspecting torque, apply the job-inspecting torque to all bolts in the connection. Retighten and re-inspect nuts or bolt heads turned by the job-inspecting torque. The Contractor may retighten the bolts in the connection and resubmit the connection for the specified inspection procedure.

G.2.d(3) Inspection Procedure for Direct Tension Indicators (DTI) Use the gap between the protrusions to indicate the tension in the bolt. Furnish the Engineer with one feeler gauge per 50 DTIs prior to commencing bolting. Notify the Engineer after the completion of each Activity:

Provide accommodation for the Engineer to check DTIs at any time during or after completion of snug tightening or final tensioning. Department personnel will not be required to accompany the Contractor during tightening. At the Engineer’s option, either the Engineer or the Contractor in the Engineer’s presence may operate the tapered leaf thickness (feeler) gauge within the procedures below. Use the following procedure for inspection of bolting operations with DTIs:

snug tight. Remove and replace DTIs with more than 50 percent of the protrusions crushed

steel member surfaces

into a randomly selected 10 percent of the DTIs and at least 2 DTIs in each connection to inspect the tightened bolts in the Structure. Measure the gap between the washer and the bolt head in the spaces between the protrusions using the 0.005 inch tapered leaf thickness

manufacturer with the exception of either:

be satisfied. Do not tighten DTIs beyond crushing of the protrusion.

established by an accepted fastener installation Plan per 2402.3G.2.c(1), “Bolt Tension.”

half of the spaces between the protrusions of a DTI, retighten the bolt and retest. There is no allowance for DTIs not satisfying the inspection requirements of DTIs as recommended by the manufacturer, except as modified in condition (3) above

spaces between the protrusions of more than 10 percent of DTI in an individual connection during the inspection, replace the affected bolts until less than 10 percent of all DTIs in the connection satisfy condition (3) above. Bolts satisfying the following conditions do not count towards the 10 percent allowance:

presence of the Engineer

elongation or fully crushing all the protrusions

established by an accepted fastener installation Plan per 2402.3G.2.c(1), “Bolt Tension” allows for all entries to be rejected G.3 Connections Using Pin Bolts Install pin bolts in accordance with 2402.3G.2.a, “General,” 2402.3G.2.b, “Bolted Parts,” and the following: Provide a special tool capable of the following to drive the pin bolts:

pinning and bolting the Work

before the pin tail breaks Provide a device capable of indicating the actual bolt tension to test the pin bolts before use. Provide at least 3 typical bolts of each size and length for tests from the supply of bolts used in the Work. Test other bolts during the bolting operation, as directed by the Engineer . Use the same installation tool used for tightening and swaging the bolts for the field connections to apply tension in the bolts during the testing procedures. Recover the expendable pin tails from the driving tool as the pin tails break from the bolt. Do not allow expendable pin tails from the driving tool to drop and create hazards. Obtain the Engineer’s approval of the testing and installation procedures for pin bolts. H Setting Anchor Bolts Unless the Contract requires otherwise, drill holes for anchor bolts to the diameter and depth shown on the Plans. Accurately set and fix the bolts with Portland cement grout that completely fills the holes. During freezing weather, the Contractor may use other products, as approved by the Engineer, to set and fix the bolts. Set nuts for anchor bolts as shown on the Plans and provide for clearance where required. Center punch the bolt thread at the face of the nuts to upset the thread and prevent back -off. Use templates to accurately set anchor bolts at the proper location and elevation that are to be cast in the concrete.

I Bearing Assemblies and Hangers Plumb rocker bearings and hangers at 45°F. Consider elongation resulting from total load deflection when setting these devices. J Shear Connectors Provide shear connections (also referred to as shear studs or stud welded fasteners) in accordance with 3391, “Fasteners.” Install shear connectors at the locations shown in the Plan after the decking falsework has been installed. The surface must be dry and free of excessive rust, mill scale, pits, scale, oil, paint, and other debris. Shear connector welding is not allowed under the following conditions:

Install the first two shear connectors at the beginning of each shift in the presence of the Engineer. Where possible, use automatic stud welding Equipment. At other locations, perform manual welding of studs in accordance with AWS D1.5, Bridge Welding Code, Chapter 7. After the weld cools, test bend the test shear connectors to an angle of approximately 30 degrees from the original angle by means of hammer strike or mechanically bending. The installation procedure must be corrected if any of the following conditions are observed:

Shear connectors rejected must be addressed by submitting a Non conformance Report (NCR) to the Engineer for acceptance prior to completing any repairs. If removal is required, any defects in the steel remaining must be ground flush to the steel surface. Retest at the rate of 2 shear connectors per failure. In addition to the initial shear connectors, test bend shear connectors at the rate of 1 per 100 shear connectors installed. If the ambient temperature is below 32°F during installation, test bend at the rate of 2 per 100 shear connectors installed. Leave shear connectors subjected to test bending in the bent position if no failure (as described above) is observed. K Expansion Joint Devices Install expansion devices in accordance with the shop drawings. Set the opening width based on the dimension provided in the Plan and the average ambient temperature based on the last 72 hours before placing concrete adjacent to the joint. Remove joint-forming Material from the joint opening. Provide a watertight expansion joint installation. Test the watertight quality of the entire length of the installed expansion joint device by filling the joint opening with water, then observe the test for 1 hour. The test may be divided into multiple segments to accommodate change in elevation over the length of the device. L Field Painting After completing the erection Work, clean and paint structural metals in accordance with 2478, “Organic Zinc-Rich Paint System,” or 2479, “Inorganic Zinc-Rich Paint System,” whichever is applicable.

2402.4METHOD OF MEASUREMENT

The Engineer will measure structural metals placed in Bridges or other Structures by weight, length, area, or unit complete in place.

A Weight The Engineer will calculate the weight of structural steel shapes, structural steel plates, steel sheets, and steel bars based on the net finished dimensions as shown on the P lans using the theoretical density of 490 pounds per cubic feet. The Engineer will not make allowances for the fabrication of girder, cambers, haunches, and sweeps, or for the machining of surfaces. The Engineer will not make deductions for open holes and Incidental bevels or chamfers. The Engineer will increase the summation of the weights of structural steel, exclusive of steel piling, by 1.5 percent to compensate for Incidental metals such as the following:

The Engineer will calculate the weight of non-Incidental metals, other than steel, using the theoretical densities shown in the AISC Manual of Steel Construction using the above measurement limitations, except the Engineer will not measure the weight of bolts, nuts, rivets, and washers used in the fabrication and erection and will not apply a percentage increase to the weight. B Length The Engineer will base linear measurement of items not specifically covered herein between the limits as shown on the Plans. C Complete Unit The Engineer will include the component parts in the measurement of the complete assembly of a unit.

2402.5BASIS OF PAYMENT

The Contract Unit Price for the specific structural steel item includes the cost of temporary support and restraint in accordance with 2402.3F, “Field Fit-up.” The Contract Unit Price for structural metals includes the weight of structural metals in a single total. The Contract Unit Price for Furnishing structural steel includes the cost of providing and fabricating in accordance with 2471, “Structural Metals”; surface preparation and shop coat painting in accordance with 2478, “Organic Zinc-Rich Paint System,” or 2479, “Inorganic Zinc-Rich Paint System,” unless otherwise required by the Contract; and delivering the Materials to the Project Site. The Contract Unit Price for Erecting structural metals includes the cost of erecting the structural metals complete in-place and, if the Plans do not include a Contract Pay Item for field coat painting, the cost of field coat painting. The Contract Unit Price for Structural steel includes the cost of providing and fabricating in accordance with 2471, “Structural Metals”; surface preparation and shop coat painting in accordance with 2478, “Organic Zinc-Rich Paint System,” or 2479, “Inorganic Zinc-Rich Paint System,” unless otherwise required by the Contract; delivering the Materials to the Project Site, and erecting the Materials. The Contract Unit Price for Elastomeric bearing pad and Elastomeric bearing assembly includes the cost of testing, providing and installing the pads or assemblies complete in-place.

The Department will pay for steel bridge construction on the basis of the following schedule: Item No. Item Unit

2402.502 Floor Drain Type ___ each

2 Elastomeric Bearing Pad each

2 Elastomeric Bearing Assembly Type ___ each

2 Bearing Assembly each

8 Structural Steel ___ pound

8 Furnishing Structural Steel ___ pound

8 Erecting Structural Metals pound