5-72 operator. Stop the cambering/curving operation if a torch oper ator fails to demonstrate the proper skill and technique necessary to prevent potential damag e to the steel. Camber stringers and girders using a “V” pattern with a 10-15 d egree included angle that extends the full web depth, less 2 inches at the apex. He at the web first beginning at the apex of the triangle and proceed ing toward the base. Begin hea ting the flange immediately after completion of the web. The Contractor may curve stringers and girders using a combinat ion of line heats applied to the edge of both flanges simultaneously with automatic track torches and "V" heats. "V" heats shall have an included angle of 15-30 degrees and a minim um height of 65% of the flange width. Apply heat to adjacent areas on both flanges sim ultaneously. Perform all cambering and curvi ng in the presence of the QAI. Heating a structural member without the QAI present shall be cause for rejection of the member. Measure and record camber and sweep after the steel has reached ambient tem perature and all stiffeners and connection plates have been welded.
504.26 Welding Qualify welders and Weld Procedure Specificatio ns in accordance with
the most recent edition of the D1.5 Code. Provide a list of qualified welders including process and position to the QAI prior to beginning fabrication. Submit the Weld Procedure Specifications to the Fabrication Engineer for review prior to beginning work. Weld Procedure Specifications previously reviewed and still valid in accordance with the D1.5 Code are acceptable without re-submission.
504.27 Welding Requirements Calibrate welding equipment at the intervals indicated in
the D1.5 Code. Meters shall be accurate within 2% throughout t he range of the WPS. Work done with equipment that is not properly calibrated will be rej ected. Provide copies of the calibration records to the QAI. The QAI can require the Contra ctor to demonstrate the accuracy of the meters at any time. Display a copy of the applicable Weld Procedure Specification a t each welding station. Weld within the parameters of the Weld Procedure Specification. Failure to display a Weld Procedure Specification at the welding station will make all we lding performed at that station subject to rejection. Perform all preheat, welding and postheat in accordance with th e D1.5 Code and this Specification. Provide the appropriate temperature indicating crayons at each workstation to verify preheat. Calibrated digital thermometers may be used with the approval of the Fabrication Engineer instead of temperature indicating crayons. 5-73 Weld flange plate and web plate butt joints, web to flange weld s, stiffener and connection plate to web welds, a nd cover plate to flange welds using an automatic weld process. Make repairs with the same process used for the original welds, except that repairs less than 12 inches in length may be m ade with a different process u sing an approved Weld Procedure Specification. Do not bl end repair welds by grinding unless the original weld requires grinding.
504.28 Welded Fabrication Each side of complete joint penetrat ion welds, once begun,
shall be welded to completion without interruption or a delay b etween passes except as necessary to maintain interpass temperature requirements. After backgouging, the groove and 3 inches on either side of the groove and through the thick ness of the steel shall be preheated in accordance with the D1.5 Code immediately before t he resumption of welding. Single-pass fillet welds may be qualified by a Fillet Weld Soun dness Test performed in accordance with the D1.5 Code as modified herein. Perform the “ T” test by welding the smallest fillet weld to be used in production on one side and t he largest fillet weld used in production on the other side of the “T”. Macroetch the test spe cimens in accordance with the requirements of Clause 5, Method of Testing Specimens, of the D 1.5 Code. Acceptance and re-testing, if required, shall be in accordance with Clause 5 T est Results Required and Retests, of the D1.5 Code. The minimum heat input for single-pass fillet welds during test ing and production shall be 35 kilojoules/in.
504.29 Welding ASTM A 709 HPS 70W Steel In addition to 504.28, use the most
recent edition of the D1.5 Code and the Fab Guide as amended he rein when welding ASTM A 709 Gr. HPS 70W. Use only consumables that produce weld meta l with diffusible hydrogen of H 8or less. Handle and store consumables in accordance with the r equirements of Clause 12 of the D1.5 Code. Pre heat in accordance with Clau se 4 of the D1.5 Code through the thickness of the steel and three inches in all dire ctions from the weldment. Failure to properly preheat the steel will result in rejection of the weld metal. Remove and re-weld rejected weldments. HPS 70W may be joined to Grade 50W steel using a Weld Procedure Specification qualified for Grade 50W steel i f the diffusible hydrogen conten t of the deposited weld metal is H 8 or less. Use minimum preheat temperature for Gr. HPS 70W in a ccordance with the D1.5 Code.
504.30 Nondestructive Testing Perform nondestructive testing i n accordance with the
D1.5 Code and these Specifications. The QAI will witness nonde structive testing. Give the QAI adequate notice to facilitate the QAI’s presence. Failure to notify the QAI will result in re-testing with the QAI present. Document nondestructive testi ng on the appropriate forms from Annex III of the D1.5 Code, or an equivalent form. 5-74
504.31 Shop Assembly Assemble stringers and girders in accorda nce with the shop
assembly drawings. Measure and record the bearing-to-bearing d imensions, the bearing-to- field-splice dimensions and the offset from the reference line dimensions as shown on the shop assembly drawings. Give th e QAI the opportunity to verify the measurements prior to disassembly.
504.32 Tolerances Dimensional tolerances for welded plate gird ers are described in the
D1.5 Code. Dimensional tolerances for rolled shapes are descri bed in AASHTO M 160 (ASTM A6). The tolerance for the length of any primary bridge member is ±1/4 inch. The bearing-to-bearing tolerance is ±1/8 inch. The bearing elevati on tolerance is ±1/8 inch. The offset tolerance for bolted field splices is ±3/4 inch.
504.33 Match marking Match mark drill assembled or ream assemb led field splice
material prior to disassembly. Preserve the match marking thro ugh field erection.
504.34 Holes for High Strength Bolts Oversize holes are not al lowed unless noted on
the Plans. Drill bolt holes full-size. Splice plates may be u sed as one-time templates to drill webs and flanges. The plates shall remain with the splice. Re place damaged plates used as a template. The Contractor may temporarily tack weld web splic e plates to the web in the middle 1/3 of the web only. Com pletely remove tack welds by gr inding and MT the tack areas. Do not tack weld flange splice plates to flanges. Holes for cross frames, diaphragms and associated connection pl ates may be punched when the thickness of the plat e is ≤ 3/8 inch. The diameter of the die shall not exceed the diameter of the punch by more than 1/16 inch. Holes shall be c lean cut, without torn or ragged edges. Make holes cylindrical and perpendicular to the member. Remove burrs from parts after drilling or reaming. Remove all visible drilling oil, lubrican ts and coolants, including water soluble lubricants and coolants from faying surfaces in accorda nce with SSPC-SP 1-Solvent Cleaning. The Contractor may thermal cut holes in bearing base plates usi ng an automatic process. Do not exceed a surface roughness of ANSI 1000 micro-inches.
504.35 Accuracy of Holes Following the completion of the drill ing of holes in a
contiguous group, with all plies of a connection in their prope r position for assembly, all bolt holes shall accept a pin 1/32 inch smaller in diameter tha n the nominal bolt hole diameter. Provide a pin of the applicable diameter for inspect ion purposes. No finished bolt hole shall be located more than 1/8 inch from its theoretical location. The repair of mislocated holes shall be subject to the approval of the Fabrication Engineer.
504.36 Shop Bolts Install shop bolts in accordance with this S pecification except that
adequately lubricated fastener assemblies that have been Rotati onal Capacity (Ro Cap)