430 METAL STRUCTURES

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430.01 DESCRIPTION.
Furnish, fabricate, transport, and erect steel beams, plate girders, trusses, grillages, columns and bents, shoes, pedestals, castings, miscellaneous steel, and incidental structural steel. Refer to Section 432 for bearings and Sections 435 and 436 for cleaning and painting new and existing structural steel, respectively.
Substitutes for Rolled Members. Fabricated shapes may be substituted for the specified rolled shape, provided the substitution is at no additional cost to the AdministrationShall mean any one of the Administrations within the Maryland Department of Transportation, as listed in GP 1.02. and the fabricated shape meets the following requirements:
(a) The moment of inertia is equal to or greater than the rolled shape for the full length of the member.
(b) The depth is greater than or equal to the rolled shape and does not decrease the designated minimum underclearance.
(c) The web or leg thickness is at least 1/2 in.
(d) The flange thickness is at least 1 in., the flange width is at least 12 in., and the width to thickness ratio does not exceed 12.
(e) It is made of the same material specified for the rolled shape.
(f) All normal criteria for creating a welded member are adhered to.
430.02 MATERIALS.
Grout       902.11(c),(d),(e)
Metals       909
Bolts       F 3125 Grade A 325, A 490
Nuts       A 536 Grade C, D, and DH
Washers       F 436
Direct Tension Indicating Washers (DTI)       F 959
430.03 CONSTRUCTION.
Unless otherwise specified, all welding and dimensional tolerances shall meet AWSAmerican Welding Society D1.5.
430.03.01 Working DrawingsStress sheets, shop drawings, fabrication details, erection plans, plans for false work, forms, centering, cribs, cofferdams and masonry layouts, bending and placing drawings, bar schedules for reinforcement steel, and any other supplementary plans or similar data that the Contractor may be required to furnish.. Refer to Section 499. If lateral bracing is required for shipping or erection, specify the details on the working drawings.
430.03.02 WorkWork shall be understood to mean the furnishing of all labor, materials, equipment, and other incidentals necessary to the successful completion of the project and the carrying out of all the duties and obligations imposed by the Contract. Scheduling. Refer to Section 499. At least two weeks prior to beginning shop work, notify the EngineerAny person designated by the Administrator or the procurement officer, acting directly or through his duly authorized representative, such representative acting within the scope of the particular duties assigned to him or of the authority given him. when and where to allow for inspection. Do not fabricate any materials unless otherwise directed. Provide weekly work schedules prior to and during fabrication as directed.
430.03.03 Facilities for Shop Inspection. Furnish all facilities for the inspection of material and workmanship in the shop. Allow the inspector free access to the required areas of the premises and provide an approved office area.
430.03.04 Material Identification. Identify main member material by heat number.
430.03.05 Mill Orders. Furnish copies of mill orders and test reports.
430.03.06 Testing. Furnish sample specimens as directed without charge.
430.03.07 Defective Material and Workmanship. The acceptance of any material and workmanship will not deter subsequent rejection. Replace or repair rejected material and workmanship as directed.
430.03.08 Marking and Shipping. Paint or mark each member with an erection mark for identification. Furnish an erection diagram with erection marks clearly delineating the orientation of diaphragms.
Erection marks for field identification of members and weight marks for members weighing over 6000 lb shall be painted on surface areas previously painted with the shop coat. Material may be loaded for shipment when the shop coat is thoroughly dry, but not less than 24 hours after the paint has been applied.
Where unpainted steel is specified for a finished structure, do not place any company’s name on the structural steel. Erection marks and inspection stamps shall appear only on the top surface of the top flange of girders, beams, and diaphragms unless otherwise directed.
Do not apply paint after the materials have been loaded for transport.
Furnish copies of material orders, shipping statements, and erection diagrams. Show the weight of the individual members on the shipping statements.
Load, transport, unload, and store structural material so that the metal is kept clean and does not become excessively stressed, deformed, or otherwise damaged.
When handling long steel members, place handling devices at approximately the quarter points. When storing and shipping members, place blocking at intervals that prevent sag and distortion. Keep beams and girders in an upright position during shipping, storage, and handling. For other members, keep the stronger axis vertical.
All girders having stiffeners the full height of the web on both sides of the web shall be adequately blocked before shipment. Locate this blocking at the quarter points and midpoint of the girder and at additional locations to ensure that the blocking interval does not exceed 25 ft.
For members too long to fit inside a truck or trailer, limit the cantilever to one quarter of the length of the member. Support members too long to comply with this requirement on dollies, additional vehicles, or other vehicles that fully support the long pieces as approved.
430.03.09 Storage of Material. Store fabricated material off the ground and protected from rust producing conditions. Keep materials free of dirt accumulation, oil, or other deleterious matter.
430.03.10 Changes and Substitutions. Do not make changes or substitutions in any approved drawing unless approved in writing by the Director, Office of StructuresBridges, culverts, catch basins, drop inlets, retaining walls, cribbing, manholes, end walls, buildings, sewers, service pipes, underdrains, foundation drains, steps, fences, and other features that may be encountered in the work and not otherwise classified..
430.03.11 Fabrication. Use bolted or welded fabrication and construction as specified or as directed.
When girders are to be curved by the heat shrinkage method, submit the proposed method.
430.03.12 Holes.
(a) Punched Holes. The diameter of the die shall not exceed the diameter of the punch by more than 1/16 in. Holes requiring enlargement shall be reamed. Provide holes that are clean cut with no torn or ragged edges. Ensure that holes punched full size or subpunched are punched so that after the steel is assembled and before any reaming is done, a cylindrical pin 1/8 in. smaller in diameter than the nominal size of the punched hole can be entered perpendicular to the face of the member, without drifting, in at least 75 percent of the contiguous holes in the same plane. If this requirement is not met, the nonconforming punched pieces will be rejected. Holes not passing a pin 3/16 in. smaller in diameter than the nominal size of the punched hole will be rejected. Drifting done during assembling is permitted only to bring the parts into position but not to the extent that holes are enlarged or distorted. If the required accuracy cannot be obtained otherwise, holes for connections shall be subpunched and reamed with the members assembled instead of being punched full size.
(b) Reamed or Drilled Holes. Holes shall be cylindrical, perpendicular to the member, and not more than 1/16 in. larger than the nominal diameter of the bolts. Where practical, direct the reamers by mechanical means. Remove burrs on the surface. Poor matching of holes will be cause for rejection. Use twist drills for reaming and drilling. If directed, take assemblies apart and remove burrs caused by drilling. Assemble connecting parts that require reamed or drilled holes, and securely hold them while reaming and drilling. Match mark them before disassembling. After holes are reamed or drilled, 85 percent of the holes in any contiguous group shall show no offset greater than 1/32 in. between adjacent thicknesses of metal.
(c) Subpunching and Reaming. Holes in all field connections and field splices of main truss or arch members, continuous beams, plate girders, and rigid frames shall be subpunched and reamed while assembled in the shop unless otherwise specified. The assembly, including camber, alignment, accuracy of holes, and milled joints shall be acceptable to the EngineerAny person designated by the Administrator or the procurement officer, acting directly or through his duly authorized representative, such representative acting within the scope of the particular duties assigned to him or of the authority given him. before reaming is started.
Holes for floor beam and stringer field end connections shall be subpunched and reamed utilizing a template or reamed while assembled.
If specified, do additional subpunching and reaming as required. The accuracy of subpunched holes shall be the same as required for punched holes.
430.03.13 Shop Assembly. Surfaces of metal that will be in contact after assembly shall be cleaned. Ensure that parts of a member are assembled, well pinned, and firmly drawn together with bolts before starting reaming or tightening of fasteners. The member shall be free from twists, bends and other deformations. Ream material that has been punched full size, if necessary, prior to tightening of fasteners. Refer to 430.03.12(c).
Parts not completely fastened in the shop shall be secured with bolts to prevent damage in shipment and handling. Members assembled in the shop for reaming of field connections shall remain assembled until the EngineerAny person designated by the Administrator or the procurement officer, acting directly or through his duly authorized representative, such representative acting within the scope of the particular duties assigned to him or of the authority given him.’s shop inspection.
430.03.14 Camber Diagram. Furnish a camber diagram showing the camber at each panel point for each truss, taken from actual measurements during truss assembly. For all beams and girders, furnish a camber diagram showing the camber at all splice points, points of dead load inflection, and any other points designated by the EngineerAny person designated by the Administrator or the procurement officer, acting directly or through his duly authorized representative, such representative acting within the scope of the particular duties assigned to him or of the authority given him..
Stringers shall be cambered to the specified dimensions, when measured after completion of all shop welding. The maximum tolerance for camber is zero under to 3/4 in. over.
Make provisions for dead load deflections, fabricating tolerances, and irregularities at all points along all stringers so that the superstructure concrete may be placed to match the profile grade line.
430.03.15 Match Marking. Match mark connecting parts assembled in the shop for the purpose of reaming holes in field connections. Furnish a diagram showing these marks.
430.03.16 Use of High Strength Bolts and Lock-Pin and Collar Fasteners. Use high strength bolts and lock-pin and collar fasteners unless otherwise specified. Unfinished bolts or machine bolts may be used for the temporary erection of structural steel. Replace them with high strength bolts, lock-pin and collar fasteners, or welding for final erection. Use turned bolts only when specified. Draw the heads, nuts, and washers tightly against the work. Where bolts or lock-pin and collar fasteners are used in beveled surfaces, provide beveled washers to give full bearing to the head, nut, or collar except as otherwise specified in 430.03.17. Where high strength bolt assemblies are used for joint connections, perform the additional testing specified by the Office of Materials Technology.
430.03.17 High Strength Bolt Joint Requirements.
(a) Use only one grade of bolts, nuts, and washers in a structure. Bolts may be supplied from various manufacturers provided that each bolt of a given length and diameter is made by the same manufacturer. Nuts and washers may be supplied from different manufacturers provided that the same manufacturers make all the respective nuts and washers to be used throughout the structure on all bolts having the same diameter. All bolts, nuts, and washers used with A 709, Grade 50W steel shall meet F 3125 Grade A 325, Type 3.
(b) The slope of surfaces of bolted parts in contact with the bolt head and nut shall not exceed 1:20 with respect to a plane normal to the bolt axis. Where an outer face of the bolted parts has a slope of more 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. When assembled, bolted parts shall fit solidly together and shall not be separated by gaskets or any other compressible material. The holes shall be truly cylindrical and at right angles to the surface of the metal so that both head and nut bear squarely against the metal. When assembled, all joint surfaces including those adjacent to the bolt heads, nuts, or washers, shall be free of scale (except tight mill scale), dirt, burrs, and other deleterious material and defects that would prevent solid seating of the parts. Contact surfaces within joints shall be free of oil, lacquer, and rust inhibitor. Refer to 435.01.01 for contact surfaces to be painted.
(c) When all bolts in the joint are tight, every bolt shall conform to the minimum installation tension specified for its size by the Office of Material Technology. When field conditions prevent tightening at the nut, bolts may be tightened at the head, provided that the nut is prevented from turning. Place a washer under the element (nut or bolt head) turned in tightening. Threaded bolt connections shall be tightened by the turn-of-nut method unless DTI’s are opted for use. If impact wrenches are used, they shall be of adequate capacity and have a sufficient supply of air to perform the required tightening of each bolted connection.
(d) To provide the bolt tension specified in 430.03.17(c), first bring enough bolts to a snug tight condition ensuring that the parts of the joint are in full contact with each other. Snug tight is defined as the tightness attained by a few impacts of an impact wrench or the full effort of a man using an ordinary spud wrench. Place bolts in any remaining holes in the connection and bring to snug tightness. Then additionally tighten all bolts in the joint with tensioning progressing systematically from the most rigid part of connection to the free edges. Ensure that there is no rotation of the part not turned by the wrench during this operation.
After all bolts in the joint have been tightened to a snug tight condition as described above, tighten the joint by the applicable amount of nut rotation specified in the Nut Rotation from Snug Tight Condition table below. All bolt assemblies in the completed structure shall have full thread engagement, which is accomplished when the end of the bolt is flush with or extends beyond the outer face of the nut.
NUT ROTATION FROM SNUG TIGHT CONDITION
DISPOSITION OF OUTER FACES OF BOLTED PARTS
Bolt length (as measured from underside of head to extreme end of bolt) Both faces normal to bolt axis One face normal to bolt axis and other face sloped not more than 1:20 (beveled washer not used) Both faces sloped not more than 1:20 from normal to bolt axis (beveled washers not used)
Up to and including 4 diameters 1/3 turn 1/2 turn 2/3 turn
Over 4 diameters but not exceeding 8 diameters 1/2 turn 2/3 turn 5/6 turn
Over 8 diameters but not exceeding 12 diameters 2/3 turn 5/6 turn 1 turn
NOTE 1: This table is for coarse thread, heavy hexagon structural bolts of all sizes and lengths and heavy hexagon semifinished nuts.
NOTE 2: Nut rotation is rotation relative to bolt regardless of the element (nut or bolt) being turned. Tolerance on rotation: ±30 degrees for bolts installed by 1/2 turn or less, and ±45 degrees for bolts installed by 2/3 turn or more.
(e) Inspection. The EngineerAny person designated by the Administrator or the procurement officer, acting directly or through his duly authorized representative, such representative acting within the scope of the particular duties assigned to him or of the authority given him. will be present during the installation and tightening of bolts to determine that the tightening procedure is followed and all bolts are properly tightened.
Provide a sufficient number of safe working platforms at splices for checking torque requirements. Maintain the platforms until all checking is complete and the splice is accepted.
Turn of Nut Method. Provide a calibrated, dial torque wrench to be used as the inspection wrench and a calibrated bolt tension calibrator. Calibrate both devices annually or as necessary. Both shall be as approved.
Conduct the following inspections unless otherwise specified.
(1) Three bolts of the same size, length, and condition as those under inspection shall be placed individually in the bolt tension calibration device. Place a washer under the part turned in tightening each bolt.
(2) Tighten each of the three bolts in the calibration device by any convenient means to the tension specified for its size. Then use the inspecting wrench to further tighten the bolt and determine the torque necessary to turn the nut or head 5 degrees (approximately 1 in. at 12 in. radius). Use the average torque measured in the tests of three bolts as the job inspecting torque to be used in the manner specified in (3).
(3) Use the inspecting wrench to inspect bolts represented in the sample above that have been tightened in the structure. Apply the job inspecting torque in the tightening direction to 10 percent of the bolts but not less than two bolts selected at random in each connection. If no nut or bolt head is turned, the connection will be accepted as properly tightened. If any nut or bolt head is turned, apply the job inspecting torque to all bolts in the connection; and tighten and reinspect all bolts whose nut or head is turned. Alternatively, the fabricator or erector may opt to retighten all of the bolts in the connection and then resubmit the connection for the specified inspection.
(f) Do not reuse bolts, nuts, or washers that were previously torqued to installation tension as described in (d) or (e) above.
430.03.18 Lock-Pin and Collar Fastener Requirements.
(a) Ensure that lock-pin and collar fasteners meet 430.03.17 for one manufacturer, weathering characteristics, sloped surfaces, and applicable inspection.
(b) A representative sample of at least three sets of lock-pin and collar fasteners of each diameter, length, and grade shall be checked at the job site in a device capable of indicating bolt tension. The test assembly shall include flat hardened washers, if required in the actual connection, arranged as in the actual connections to be tensioned. The calibration test shall demonstrate that each assembly develops a tension at least 5 percent greater than the tension required for the comparable F 3125 Grade A 325 or A 490 bolt. Follow manufacturer’s installation procedure for installation of bolts in the calibration device and in all connections. Perform periodic retesting when directed.
(c) Install fasteners in all holes of the connection and initially tighten sufficiently to bring all plies of the joint into firm contact but without yielding or fracturing the control or indicator element of the fasteners. Then additionally tighten all fasteners, progressing systematically from the most rigid part of the connection to the free edges in a manner that will minimize relaxation of previously tightened fasteners. In some cases, proper tensioning of the fasteners may require more than a single cycle of systematic partial tightening prior to final twist off of the control or indicator element of individual fasteners.
430.03.19 Welding. Provide welding of structures and welding qualifications as specified and per American Welding Society (AWSAmerican Welding Society) BridgeA structure including supports erected over a depression or an obstruction, such as water, highway, or railway, and having a track or passageway for carrying traffic or other moving loads, and having an opening measured along the center of the roadway of more than 20 feet between undercopings of abutments or spring lines of arches, or extreme ends of openings for multiple boxes; it may also include multiple pipes, where the clear distance between openings is less than half of the smaller contiguous opening. For lengths, all dimensions shall be parallel to the center line of the roadway. The dimensions of handrails will not be taken into account in measuring bridge lengths. Any bridge or highway grade separation structure includes the connecting highways, substructure, superstructure, roadway approaches, entrance plazas, interchanges, overpasses, underpasses, and other structures which the Administration may deem necessary together with all property rights, easements, franchises, and interests acquired by the Administration for the construction and operation of the bridge. Welding Code D1.5 (AWSAmerican Welding Society D1.5) unless otherwise directed. These provisions apply to both shop and field welding.
Ensure that all welders, welding machine operators, and tackers employed to work on AdministrationShall mean any one of the Administrations within the Maryland Department of Transportation, as listed in GP 1.02. projects are qualified as follows:
(a) AWSAmerican Welding Society Qualifications. Welders shall take tests approved by the Structure Committee for Economic Fabrication (SCEF) per AWSAmerican Welding Society D1.5 as administered by an AWSAmerican Welding Society Accredited Test Facility (ATF).
(b) Fabricator Qualifications. Fabricators performing work for AdministrationShall mean any one of the Administrations within the Maryland Department of Transportation, as listed in GP 1.02. projects shall be qualified under the American Institute of Steel Construction (AISCAmerican Institute of Steel Construction) CertificationA document which verifies that the material and work complies with the applicable specifications and includes the actual test results to confirm the statement. The contents of the certification shall be on the Contractor's/vendor's/manufacturer's letterhead or approved document and shall be duly signed by a company officer. Certifications for metal products, when required, shall include a statement that the material was melted and manufactured in the United States except as provided in Section 165 of the Surface Transportation Assistance Act of 1982, as amended by Section 1041(a) and 1048(a) of the Intermodal Surface Transportation Efficiency Act of 1991 with regard to the furnishing and coating of iron and steel products. A nationwide waiver for this provision has been granted for pig iron and processed, pelletized, and reduced iron ore. Program for Steel BridgeA structure including supports erected over a depression or an obstruction, such as water, highway, or railway, and having a track or passageway for carrying traffic or other moving loads, and having an opening measured along the center of the roadway of more than 20 feet between undercopings of abutments or spring lines of arches, or extreme ends of openings for multiple boxes; it may also include multiple pipes, where the clear distance between openings is less than half of the smaller contiguous opening. For lengths, all dimensions shall be parallel to the center line of the roadway. The dimensions of handrails will not be taken into account in measuring bridge lengths. Any bridge or highway grade separation structure includes the connecting highways, substructure, superstructure, roadway approaches, entrance plazas, interchanges, overpasses, underpasses, and other structures which the Administration may deem necessary together with all property rights, easements, franchises, and interests acquired by the Administration for the construction and operation of the bridge. Fabricators or BridgeA structure including supports erected over a depression or an obstruction, such as water, highway, or railway, and having a track or passageway for carrying traffic or other moving loads, and having an opening measured along the center of the roadway of more than 20 feet between undercopings of abutments or spring lines of arches, or extreme ends of openings for multiple boxes; it may also include multiple pipes, where the clear distance between openings is less than half of the smaller contiguous opening. For lengths, all dimensions shall be parallel to the center line of the roadway. The dimensions of handrails will not be taken into account in measuring bridge lengths. Any bridge or highway grade separation structure includes the connecting highways, substructure, superstructure, roadway approaches, entrance plazas, interchanges, overpasses, underpasses, and other structures which the Administration may deem necessary together with all property rights, easements, franchises, and interests acquired by the Administration for the construction and operation of the bridge. and Highway Metal Component Manufacturers and the following:
(1) Meet certification requirements of the Standard for Steel Bridges and BridgeA structure including supports erected over a depression or an obstruction, such as water, highway, or railway, and having a track or passageway for carrying traffic or other moving loads, and having an opening measured along the center of the roadway of more than 20 feet between undercopings of abutments or spring lines of arches, or extreme ends of openings for multiple boxes; it may also include multiple pipes, where the clear distance between openings is less than half of the smaller contiguous opening. For lengths, all dimensions shall be parallel to the center line of the roadway. The dimensions of handrails will not be taken into account in measuring bridge lengths. Any bridge or highway grade separation structure includes the connecting highways, substructure, superstructure, roadway approaches, entrance plazas, interchanges, overpasses, underpasses, and other structures which the Administration may deem necessary together with all property rights, easements, franchises, and interests acquired by the Administration for the construction and operation of the bridge. and Highway Metal Components and,
(2) Possess certification in either Simple, Intermediate or Advanced Bridges or as a Manufacturer of Components, depending on type of structural item required.
(3) Fabricators producing fracture-critical members or intermediate or advanced bridges shall meet specific supplemental requirements as determined.
(4) Approved fabricators may issue in-house welder qualifications for shop and field welding.
(c) Steel Stud Shear Developer Qualifications. Steel Stud Shear Developer welders will be inspected and approved at the time of installation per above.
All field welders shall possess a current AWSAmerican Welding Society welder’s qualification card or a fabrication facility qualification card approved by the Office of Materials Technology (OMT). This card shall be available for inspection at all times.
Welding members carrying primary stress shall be by the submerged arc method (SAW) unless otherwise specified. For material thickness 2 in. and greater, the narrow gap electro slag welding process (ESW) may be substituted. Members carrying primary stress are specified in 909.01.
After fabrication, welding will not be permitted on tension flanges for attachments (e.g, metal forms, ty screws) except for steel stud shear developers. Welding transversely across tension flanges of beams or girders will be cause for rejection, unless otherwise specified.
When field welds area required, mask 1-1/2 in. back from the weld area and do not paint.
430.03.20 Inspection of Fabricated Metal StructuresBridges, culverts, catch basins, drop inlets, retaining walls, cribbing, manholes, end walls, buildings, sewers, service pipes, underdrains, foundation drains, steps, fences, and other features that may be encountered in the work and not otherwise classified.. Meet AWSAmerican Welding Society D1.5 and the following:
An approved Quality Control Plan (QCP) must be on file with OMT prior to receiving source approval. The AdministrationShall mean any one of the Administrations within the Maryland Department of Transportation, as listed in GP 1.02. requires 30 days to review quality control plans not previously on file. The QCP shall include:
(a) Method for providing documentation.
(b) Method and frequency of performing quality control inspections.
(c) Qualifications of personnel performing quality control inspections.
Ensure that the inspection frequency is at least the minimum specified. Keep complete and current records and make available for inspection at all times.
430.03.21 Planing. Plane the top and bottom surfaces of steel slabs, base plates, and cap plates of columns and pedestals; or have the plates or slabs heat straightened. Ensure that parts of members in contact with them are faced. In planing the flat surfaces of expansion bearings, the cut of the tool shall be in the direction of expansion.
430.03.22 Abutting Joints. Ensure that abutting joints in compression members and in tension members where specified, are faced and brought to an even bearing. Where joints are not faced, limit the opening to no more than 1/8 in.
430.03.23 End Connection Angles. Floor beams, stringers, and girders having end connection angles shall be built to the exact length back-to-back of connection angles. If end connections are faced, ensure that the finished thickness of the angles is not less than specified.
430.03.24 Main Members. Principal portions of main members carrying primary stress (refer to 909.01) shall be fabricated so that the direction of stress and rolling are the same.
430.03.25 Web Plates. At web splices, ensure that the clearance between the ends of the web plates is not more than 3/8 in. Ensure that the clearance at the top and bottom ends of the web splice plates is not more than 1/4 in.
430.03.26 Bent Plates. Unwelded, cold bent, load carrying, rolled steel plates shall be taken from the stock plates so that the bend line will be at right angles to the direction of rolling, except that cold bent ribs for orthotropic deck bridges may be bent in the direction of rolling if approved and shall meet the following:
MINIMUM COLD-BENDING RADII
A 709 Grades Thickness, in. (t)
Up to 3/4 Over 3/4 to 1, incl. Over 1 to 2, incl. Over 2
36 1.5t 1.5t 1.5t 2.0t
50 1.5t 1.5t 2.0t 2.5
50W 1.5t 1.5t 2.0t 2.5
HPS70W 1.5t 1.5t 2.5 3.0t
100 1.75t 2.25 4.5t 5.5t
100W 1.75t 2.25 4.5t 5.5t
(a) Bend so that no cracking of the plate occurs. Minimum bend radii, measured to the concave face of the metal shall meet the following.
(b) For brake press forming, the lower die span should be at least 16 times the plate thickness. Multiple hits are advisable.
(c) If a shorter radius is essential, bend the plates at a temperature no greater than 1200 F. Hot bent plates shall be taken from stock so that the bend line will be at right angles to the direction of rolling.
(d) Before bending, round the corners of the plate to a radius of 1/16 in. throughout the portion of the plate where the bending is to occur.
430.03.27 Erection Plan. Submit an erection plan for approval outlining erection procedure of the main members. Submit the erection plan as specified in Section 499 and to the Director, Office of StructuresBridges, culverts, catch basins, drop inlets, retaining walls, cribbing, manholes, end walls, buildings, sewers, service pipes, underdrains, foundation drains, steps, fences, and other features that may be encountered in the work and not otherwise classified., at least 30 days prior to beginning erection. Include the numbers and types of equipment to be used including crane capacity, location of crane for lifting, falsework when required, and main member erection sequence and weight.
Ensure that all wheels and outriggers of a crane or wheels of a structural steel delivery truck are at a minimum distance from the rear face of an abutment equal to the vertical distance from the top of a spread footing or to the original groundline if the footing is on piles. Ensure that no other heavy construction equipment operates within this distance from the rear face of abutments.
Erect bridges with continuous main members in a manner providing the proper reactions, and avoiding overstressing main members.
When preparing erection plans and procedures, take into account the restrictions imposed by the Water Resources AdministrationShall mean any one of the Administrations within the Maryland Department of Transportation, as listed in GP 1.02. relative to pollution or disturbance of existing waterways.
430.03.28 Falsework. Comply with the provisions specified in TC-4.01 and Section 499. Build and maintain the falsework in accordance with the approved falsework plans. Any changes subsequent to initial approval shall be proposed through the ContractorAny person having a Contract with a procurement agency. Contractor does not include an employee with an employment Contract, or an employee organization with a collective bargaining agreement.’s professional engineer and be as approved.
Before permitting any loads to be placed on falsework, the EngineerAny person designated by the Administrator or the procurement officer, acting directly or through his duly authorized representative, such representative acting within the scope of the particular duties assigned to him or of the authority given him. shall receive written certification by the ContractorAny person having a Contract with a procurement agency. Contractor does not include an employee with an employment Contract, or an employee organization with a collective bargaining agreement.’s professional engineer that the falsework system has been assembled in conformance with the approved falsework drawings. This certification shall be accompanied by a Certificate of Compliance stating that all manufactured materials and assemblies fully comply with the falsework design and plans. The EngineerAny person designated by the Administrator or the procurement officer, acting directly or through his duly authorized representative, such representative acting within the scope of the particular duties assigned to him or of the authority given him. may either accept the certificate or invoke any provision of GP-5.08. Perform all tests required at no additional cost to the AdministrationShall mean any one of the Administrations within the Maryland Department of Transportation, as listed in GP 1.02..
In addition to protective measures shown on the falsework plans, the EngineerAny person designated by the Administrator or the procurement officer, acting directly or through his duly authorized representative, such representative acting within the scope of the particular duties assigned to him or of the authority given him. may direct that further protection of falsework be provided against accidental collision by highway or construction traffic and equipment, traffic vibration, flood waters or high winds, etc., that are necessary for public safety and protection of the work.
430.03.29 Damaged or Defective Material. Submit a written procedure for correcting damaged or defective material to the Director, Office of StructuresBridges, culverts, catch basins, drop inlets, retaining walls, cribbing, manholes, end walls, buildings, sewers, service pipes, underdrains, foundation drains, steps, fences, and other features that may be encountered in the work and not otherwise classified.. Do not proceed with corrections until approved. The EngineerAny person designated by the Administrator or the procurement officer, acting directly or through his duly authorized representative, such representative acting within the scope of the particular duties assigned to him or of the authority given him. will inspect damaged or defective material before and after correction. Make corrections in the presence of the EngineerAny person designated by the Administrator or the procurement officer, acting directly or through his duly authorized representative, such representative acting within the scope of the particular duties assigned to him or of the authority given him..
430.03.30 Assembling Steel. Carefully handle material without bending, breaking, or otherwise damaging parts. Before assembly, clean the bearing surfaces and those to be in permanent contact. Before beginning field bolting and welding, adjust the structure to correct grade and alignment, and properly regulate the elevations of panel points (ends of floor beams). Fill half the holes in splices and field connections using bolts and cylindrical erection pins (40 percent bolts and 10 percent pins) before torquing high strength bolts. If the member will carry traffic during erection, fill three fourths of the holes before torquing. Cylindrical erection pins shall be 1/32 in. larger than the diameter of the fasteners.
430.03.31 Anchor Bolts. Per 909.06. Do not cast anchor bolts in the concrete. Create a template to locate the anchor bolt holes and use it to shift the reinforcement prior to placing the concrete to eliminate conflicts between the reinforcement and the anchor bolt holes.
Set anchor bolts in round holes drilled or cast in the concrete. Accurately position bolts by using templates set to correct location and alignment to ensure proper span lengths, and carefully set tops of bolts to proper elevation. Unless otherwise noted, install bolts plumb or normal to the finished bearing surface of the masonry.
Bolts shall have the portion below the bridge seat swedged. Drill or cast holes to a diameter at least 1 in. larger than the bolt diameter.
Do not paint anchor bolts, nuts, and washers.
After anchor bolts are finally and correctly positioned, completely fill the holes with grout; however, do not grout until all structural steel is set in its final position. After the masonry plates or shoes are set, use the same grout to fill the space between the bolts and the round holes of fixed plates and shoes. Do not fill slotted holes in expansion devices unless specified.
Maintain an air temperature of at least 40 F around the mortar surface for a period of three days unless otherwise recommended by the manufacturer.
When mortar filling is used, first check the depth of the hole by inserting and withdrawing the bolt. Then partially fill the hole with mortar, and immediately insert the bolt by forcing with uniform pressure or light blows from a hammer (flogging and running is prohibited) so that excess mortar is pushed out at the top of the hole. Remove excess mortar.
Set the bolt to project approximately 1/2 in. above the nut and ensure that it is threaded to approximately 1/2 in. below the nut in their final position.
Set rockers or expansion plates with slotted holes with the proper tilt or offset as determined by the temperature prevailing at the time and so that they will be in their midway position at 68 F or as specified.
430.03.32 Maintenance of Concrete. Keep all exposed concrete surfaces free from stains and discoloration. Prevent staining of the finished concrete surfaces where unpainted structural steel is specified. Remove any stains and restore the concrete to its original color.
430.03.33 Safety Hazards. Perform gas detection in and ventilation of confined spaces as specified in TC-3.04.
430.04 MEASUREMENT AND PAYMENT.
The payment will be full compensation for all high strength bolt and lock-pin and collar fastener assembly testing and for all material, labor, equipment, tools, and incidentals necessary to complete the work.
430.04.01  Fabricated Structural Steel will not be measured but will be paid for at the Contract lump sum price.
430.04.02  Fabricated Structural Steel will be measured and paid for at the Contract unit price per pound computed on the theoretical weight.
Where measurement and payment of Fabricated Structural Steel is based on weight, the weight will be computed on the basis of the net finished dimensions of the parts as shown on the approved working drawings, deducting for copes, cuts, clips, and all open holes.
Computations will be made on the basis of the following:
MATERIAL POUNDS PER CUBIC FOOT
Aluminum, cast or wrought 173.0
Bronze, cast 536.0
Copper alloy 536.0
Copper, sheet 558.0
Iron, cast 445.0
Iron, malleable 470.0
Lead, sheet 707.0
Steel, rolled, cast, copper bearing,

silicone, nickel and stainless

490.0
Zinc 450.0
The weight of rolled shapes will be computed on the basis of their nominal weight per foot as specified in the Contract DocumentsThe written agreement executed between an Administration and the successful bidder, covering the performance of the work and furnishing of labor, equipment and materials, by which the Contractor is bound to perform the work and furnish the labor, equipment and materials, and by which the Administration is obligated to compensate him therefore at the mutually established and accepted rate or price. The Contract Documents shall include the Invitation for Bids, Notice to Contractors, Instructions to Bidders, Proposal, Contract Forms and Bonds, General Provisions, Specifications, Supplemental Specifications, all Special Provisions, all Technical Provisions, all Plans and Notices to Proceed, also any written Change Orders and Supplemental Agreements that are required to complete the construction of the work in an acceptable manner, including authorized extension thereof or listed in handbooks.
The weight of rolled shapes will be computed on the basis of their nominal weight for their width and thickness as specified, plus an estimated overrun computed as half the permissible variation in thickness and weight as tabulated in A 6.
The weight of all shop weld metal (not included in weighed unit) and field weld metal will be computed on the basis of the theoretical volume from dimensions of the welds.
The weight of temporary erection bolts, shop and field paint, boxes, crates and other containers used for shipping, and materials used for supporting members during transportation and erection is excluded from the calculation of weight for payment.
Structural members or materials which fail to conform to requirements of tests and all materials rejected as a result of these tests will not be measured or paid for under any method of payment.
430.04.03  When a pay item for Fabricated Structural Steel is not specified, the fabricated structural steel will not be measured but the cost will be incidental to other pertinent items.
430.04.04  Rotational capacity testing for high strength bolt assemblies will not be measured but the cost will be incidental to the Contract price for the Fabricated Structural Steel item or other pertinent items specified.