SECTION STRUCTURAL STEEL FRAMING

Transcription

1 SECTION STRUCTURAL STEEL FRAMING PART 1 - GENERAL 1.1 SUMMARY A. Section includes steel elements indicated on the structural drawings. 1.2 SUBMITTALS A. Product Data: Submit copies of producer's or manufacturer's specifications and installation instructions for the following products. Include laboratory test reports and other data as required to show compliance with these specifications (including specified standards): 1. Structural steel (each type), including certified copies of mill reports covering the chemical and physical properties, when requested. 2. Structural steel primer paint. 3. Shrinkage-resistant grout. 4. Provide a schedule of shop drawing submittals for the architect s information at least 30 days prior to the first shop drawing submittal. B. Shop Drawings: 1. Submit Shop Drawings, including complete details and schedules for fabrication and assembly of members. a. The Fabricator shall either employ or retain a Structural Engineer licensed in the State of Illinois (Fabricator s Engineer). All structural steel shop drawings shall be completed under the direct supervision and review of the Fabricator s Engineer. b. The Fabricator s Engineer shall seal, date and submit a letter simultaneously with the first submittal of structural steel shop drawings stating the following: All structural steel shop drawings prepared for this project either have been or will be prepared under my direct supervision and review. c. Structural steel shop drawings will not be reviewed by the Architect until the Fabricator s Engineer s letter is received. 2. Include details of cuts, connections, camber, holes, stiffeners and other pertinent data. Indicate welds by standard AWS symbols, and show size, length, and type of each weld. 3. Provide setting drawings and directions for the installation of anchor rods and other anchorages to be installed by others. C. Connection Calculations: 1. Submit calculations for framed beam connections and other connections not completely detailed. Calculations shall be stamped by the Fabricator s Engineer. Calculations shall URBAN PREP HIGH SCHOOL STRUCTURAL STEEL FRAMING

2 be reviewed for general conformance with the design intent and shall be submitted for record only. 2. Calculations shall be submitted with the first shop drawing submittal, and shall be crossreferenced with all shop drawing submittals. 3. Shop drawings will not be reviewed without the submittal of coordinated connection calculations. D. Certification: 1. Submit certification that welders to be employed in the Work have satisfactorily passed AWS qualification tests. a. If recertification of welders is required, retesting shall be the Contractor's responsibility. 1.3 QUALITY ASSURANCE A. Codes and Standards: Comply with the provisions of the following, except as otherwise specified. 1. AISC "Load and Resistance Factor Design Specification for Structural Steel Buildings," latest edition, including Appendices and Supplements thereto. 2. AISC Code of Standard Practice for Steel Buildings and Bridges, latest edition, with the following modifications: a. In the Glossary, the term Owner s Designated Representative for Design shall be defined as the Architect. b. In Section 3.1.1, add the following to the end of the section: Where reaction forces are given on the design drawings, Fabricator is responsible for designing stiffeners and/or doublers if necessary. c. In Section 3.1.2, add the following to the end of the section: Review of submitted connections by the Architect is limited to general conformance with the contract documents and the design intent. The Fabricator shall bear full responsibility for connection design. d. Delete Section 3.3 in its entirety and substitute the following: All situations which, in the opinion of the Contractor, appear to be deficiencies, omissions, contradictions, or ambiguities in the Design Drawings and Specifications, shall be brought to the attention of the Architect. Design Drawings and Specifications will be corrected or a written interpretation of the alleged deficiency, omission, contradiction, or ambiguity shall be made by the Architect before the affected work proceeds. When discrepancies exist between the Design Drawings and the Specifications, the Architect shall be informed in writing, and the Architect shall identify what shall govern. When discrepancies exist between scale dimensions in the Design Drawings and the figures written in them, the figures shall govern. When discrepancies exist between the structural design drawings and the architectural, electrical or mechanical design drawings or Design Drawings for other trades, the Architect shall advise what shall govern. e. Delete Section 3.6 in its entirety and substitute the following: Design drawings released as part of a bid package shall not be considered to be released for URBAN PREP HIGH SCHOOL STRUCTURAL STEEL FRAMING

3 purchase of material or fabrication without 10 days prior notification to the Architect of intent to purchase or fabricate. f. Delete section 4.4 in its entirety and substitute the following: 4.4 Except as provided in Section 4.5, the Shop and Erection Drawings shall be submitted to the Architect and the Board s Designated Representative for Construction for review and approval. Approved Shop and Erection Drawings shall be individually annotated by the Architect and the Board s Designated Representative for Construction as either approved or approved subject to corrections noted. When so required, the Fabricator shall subsequently make the corrections noted and furnish corrected Shop and Erection Drawings to the Architect and the Board s Designated Representative for Construction. Shop drawings submitted to the Architect shall allow for 14 calendar days for review Approval of the Shop and Erection Drawings is subject to corrections noted and similar approvals shall indicate the Fabricator has correctly interpreted the intent of the Contract Documents in the preparation of those submittals. Such approval shall not relieve the Fabricator of the responsibility for either the accuracy of the detailed dimensions in the shop and erection drawings or the general fit-up of parts that are to assembled in the field. 3. AISC "Specification for Structural Joints Using ASTM A 325 or A 490 Bolts" approved by the Research Council on Structural Connections of the Engineering Foundation. 4. AWS D1.1 "Structural Welding Code - Steel". 5. ASTM A 6 "General Requirements for Delivery of Rolled Steel Plates, Shapes, Sheet Piling and Bars for Structural Use." 6. AAMA TIR-A11 Maximum Allowable Deflection of Framing for Framing Systems for Building Cladding Components at Design Wind Loads. B. Qualifications for Welding Work: Qualify welding processes and welding operators in accordance with the AWS Qualification requirements. C. Design of Members and Connections: Unless otherwise indicated, provide standard AISC framed beam connections using high strength bolts in shear/bearing type connections with threads included in the shear plane designed for the beam reactions indicated or if not indicated, provide a least three fourths of the uniform load carrying capacity of the beam. 1. Provide a minimum of two (2) bolts at each connection. 2. Provide connections at least one half the depth of the member. 3. Provide slip-critical bolted connections in bolts installed in over-sized holes, in connections subject to fatigue, and in connections in which a combination of bolts and welds resist applied loads (weld only after bolts are tightened). D. Fabricator Qualifications: Engage a firm experienced in fabricating structural steel similar to that indicated for this Project and with a record of successful in-service performance, as well as sufficient production capacity to fabricate structural steel without delaying the Work. 1. Fabricator must participate in the AISC Quality Certification Program and be designated an AISC-Certified Plant as follows: URBAN PREP HIGH SCHOOL STRUCTURAL STEEL FRAMING

4 a. Category: Category SBD, conventional steel building structures. E. Erector Qualifications: Engage a firm with a minimum of ten years experience in erecting structural steel for projects of similar type and scope and with a record of successful completion. 1.4 DELIVERY, STORAGE AND HANDLING A. Deliver materials to the site at such intervals to ensure uninterrupted progress of the Work. B. Deliver anchor rods and anchorage devices in ample time to not delay that Work. C. Keep members off the ground. Protect steel members and packaged materials from corrosion and deterioration. D. Do not store materials on the structure in a manner that might cause distortion or damage to the members or the supporting structures. Repair or replace damaged materials or structures as directed. 1.5 QUALITY CONTROL A. The Owner will engage an independent testing and inspection agency to inspect high-strength bolted connections and welded connections and to perform tests and prepare test reports. B. The Owner s Testing Agency will conduct and interpret the tests and state in each report whether the test specimens comply with the requirements, and specifically state any deviations there from. C. The Architect reserves the right to reject material not complying with specified requirements. D. Correct deficiencies in structural steel work which inspections and laboratory test reports have indicated to be not in compliance with requirements. The Owner may have additional tests performed, at Contractor's expense, as may be necessary to reconfirm any non-compliance of the original Work, and as may be necessary to show compliance of corrected Work. E. Contractor s Responsibilities 1. Notify Owner s Testing Agency sufficiently in advance of operations to allow for his assignment of personnel and scheduling of tests. 2. Coordinate with Agencies personnel; provide access to Work and to plant operations. 3. Furnish casual labor and facilities to provide access to Work to be tested to facilitate inspections and tests. F. Shop and Field Testing Program By Owner s Testing Agency: The following testing program outline is for information only and may not be comprehensive. 1. Material and Welder Certification: a. Review each Contractor's mill reports covering chemical and physical properties of steel for conformance with the applicable ASTM specification. URBAN PREP HIGH SCHOOL STRUCTURAL STEEL FRAMING

5 b. Review each Contractor's field welder certification for conformance with AWS certification requirements. 2. Bolted Connections: Bolted connections shall be inspected according to RCSC s Specification for Structural Joints Using ASTM A 325 or A 490 Bolts. a. Visually inspect bolted connections. b. Perform calibrated wrench tests on all bolted, slip critical connections. c. For connections not designated as slip critical, inspect connections to insure that the plies of the connected elements have been brought into snug contact. 3. Welded Connections: Welded connections shall be tested and inspected according to AWS D1.1. a. Perform visual inspection of all welded connections. b. Perform ultrasonic testing of all full penetration welds. 1) Full penetration welds of HSS members shall meet AWS Class R Acceptance Criteria. 4. Shear Connectors: Welded shear connectors shall be tested and inspected according to AWS D1.1. a. Perform visual inspection of all welded shear connectors. b. Perform bend tests if visual inspection reveals a less-than-continuous 360-degree flash. PART 2 - PRODUCTS 2.1 MATERIALS A. Metal Surfaces, General: For fabrication of work which will be exposed to view, use only materials which are smooth and free of surface blemishes including pitting, rust and scale seam marks, roller marks, rolled trade names and roughness. Remove such blemishes by grinding, or by welding and grinding, prior to cleaning, treating and application of surface finishes. B. Provide fine-grain killed steel of structural shapes within groups 4 or 5 of AISC grouping for tensile property classification. C. Steel shapes: ASTM A 992, except where other type steel is shown; ASTM A 36 for plates, bars, channels, angles and miscellaneous detail materials. D. Hollow Structural Sections: ASTM A 500, Grade B. E. Steel Pipe: ASTM A 53, Type E or S, Grade B; standard weight unless otherwise shown. F. Anchor Rods: ASTM F 1554, Grade 36, unless otherwise indicated. URBAN PREP HIGH SCHOOL STRUCTURAL STEEL FRAMING

6 G. Headed Stud Type Shear Connectors: ASTM A 108, Grade 1015 through 1020, cold-finished carbon steel; with dimensions complying with AISC Specifications. H. High-Strength Threaded Fasteners: Heavy hexagon structural bolts, heavy hexagon nuts, and hardened washers, as follows: 1. Quenched and tempered medium-carbon steel bolts, nuts and washers, complying with ASTM A 325 unless Drawings indicate ASTM A Direct tension indicator washers conforming to ASTM F 959, type 490 may be used at Contractor's option. I. Electrodes for Welding: Comply with AWS Code. J. Structural Steel Primer Paint (Except where specified otherwise): Lead and chromate free rust-inhibitive metal primer equal to Tnemec K. Structural Steel Primer Paint for Architecturally Exposed Structural Steel: Organic Zinc-rich primer; Tnemec 90-97, Tneme-Zinc. L. Non-Metallic Shrinkage-Resistant Grout: Pre-mixed, non-metallic, non-corrosive, nonstaining product containing selected silica sands, Portland cement, shrinkage compensating agents, plasticizing and water reducing agents, complying with ASTM C1107. Grout shall have a minimum compressive strength of 5000 psi at 28 days when tested in conformance with ASTM C 109. M. Masonry Anchors: 1. Where secured to flanges of member, weld on anchor rods consisting of 9" overall length, ¼" bright finished wire with 3/8" offsets to provide 4" adjustment of masonry anchors. Adjustable portion by Mason. 2. Where secured to webs of members, weld on anchors consisting of 8 gauge hot dipped galvanized angle, 7" high x 1/2 flange depth with 1" return for fastening. Provide 5" high slotted hole 3/4" from outer edge to receive wire tie wire tie by Mason. 2.2 FABRICATION A. Shop Fabrication and Assembly: 1. Fabricate and assemble assemblies in the shop to the greatest extent possible. Fabricate items of steel in accordance with AISC Specifications and as indicated on the final Shop Drawings. Provide camber. 2. Properly mark and match-mark materials for field assembly. Fabricate for delivery sequence, which will expedite erection and minimize field handling of materials. 3. Where finishing is required, complete the assembly, including welding of units, before start of finishing operations. Provide finish surfaces of members exposed in the final structure free of markings, burrs, and other defects. 4. Fabricate steel components exposed to view in the finished building from straightened steel elements in accordance with AISC "Code of Standard Practice for Steel Buildings and Bridges, Section 10. Fabricate built-up components with tight joints to close tolerance. Continuously weld, chip and grind joints eliminating water pocketing and URBAN PREP HIGH SCHOOL STRUCTURAL STEEL FRAMING

7 B. Connections: entering the assembly. Provide all welded construction except where specifically shown otherwise on drawings. Remove backing bars and run-off tabs from members exposed to view. 1. Weld or bolt shop connections, as indicated. 2. Bolt field connections, except where welded connections or other connections are indicated. Provide high-strength threaded fasteners. High-Strength Bolted Construction: Install high-strength threaded fasteners in accordance with AISC "Specifications for Structural Joints using ASTM A 325 or A 490 Bolts". 3. Welded Construction: Comply with AWS Code for procedures, appearance and quality of welds, and methods used in correcting welding work. Assemble and weld built-up sections by methods, which will produce true alignment of axes without warp. C. Shear Connectors: Prepare steel surfaces as recommended by the manufacturer of the shear connectors. Use automatic end welding of headed stud shear connectors in accordance with the manufacturer's printed instructions. D. Holes for Other Work: 1. Provide holes required for securing other Work to structural steel framing, and for the passage of other Work through steel framing members, only as shown on the final Shop Drawings. 2. Provide threaded nuts welded to framing, and other specialty items as shown to receive other Work. 3. Cut, drill, or punch holes perpendicular to metal surfaces. Do not flame cut holes or enlarge holes by burning. Drill holes in bearing plates. E. Masonry Anchors: 1. Weld to steel members as indicated on the Drawings. 2. Where spacing is not shown, provide at 16 on center on columns and 16 on center on beams and girders. 2.3 SHOP FINISHING A. General: Shop paint all steel work, except as specified hereinafter. Apply 2 coats of paint to surfaces that are inaccessible after assembly or erection. Change color of second coat to distinguish it from the first. 1. Do not paint surfaces that are to be welded or high-strength bolted with slip critical connections. 2. Do not paint steel to be covered by sprayed-on fireproofing. 3. Portions embedded in concrete or masonry need not be painted. B. Surface Preparation: Remove loose rust, loose mill scale, and spatter, slag or flux deposits. Solvent clean in accordance with SSPC SP-1 and further clean in accordance with one of the following Steel Structures Painting Council (SSPC) Specifications. URBAN PREP HIGH SCHOOL STRUCTURAL STEEL FRAMING

8 1. SP-2 "Hand Tool Cleaning." 2. SP-3 "Power Tool Cleaning." 3. SP-7 "Brush-Off Blast Cleaning." C. Painting: Immediately after surface preparation, apply structural steel primer paint in accordance with the manufacturer's instructions and at a rate to provide a uniform dry film thickness of 1.5 mils, except 3 mils dry for organic zinc rich primer. Use painting methods that will result in full coverage of joints, corners, edges and all exposed surfaces. D. Galvanizing: Galvanize steel members where indicated on the Drawings. Apply zinc coating by the hot-dip process to structural steel according to ASTM A 123. PART 3 - EXECUTION 3.1 STORAGE AND HANDLING A. Store structural steel members at the project site above ground on platforms, skids or other supports. B. Store other materials in a weather-tight and dry place until ready for use in the work. C. Store packaged material in their original unbroken package or container. 3.2 ERECTION A. Surveys: Check elevations of bearing surfaces, and locations of anchor rods and similar devices, before erection work proceeds, and report discrepancies. Do not proceed with erection until corrections have been made, or until compensating adjustments to the structural steel work have been agreed upon with the Architect. B. Anchor Rods: Furnish anchor rods and other connectors required for securing structural steel to foundations and other in-place Work. Furnish templates and other devices as necessary for presetting rods and other anchors to accurate locations. C. Setting Bases and Bearing Plates: 1. Clean bearing surfaces of bond-reducing materials and roughen to improve bond to surfaces. Clean the bottom surface of base and bearing plates. 2. Set loose and attached base plates and bearing plates for structural members on wedges or other adjusting devices. 3. Tighten anchor rods after the supported members have been positioned and plumbed. Do not remove wedges or shims; but, if protruding, cut off flush with the edge of the base or bearing plate prior to packing with grout. 4. Fill solidly between bearing surfaces and bases or plates with shrink-resistant grout to ensure that no voids remain. Grout only under conditions consistent with manufacturer s recommendations. Finish exposed surfaces, protect installed materials, and allow to cure in strict compliance with the manufacturer's instructions. D. Field Assembly: URBAN PREP HIGH SCHOOL STRUCTURAL STEEL FRAMING

9 1. Set structural frames accurately to the lines and elevations. Align and adjust the various members forming a part of a complete frame or structure before permanently fastening. Clean bearing surfaces and other surfaces that will be in permanent contact before assembly. Perform necessary adjustments to compensate for discrepancies in elevations and alignments. 2. Level and plumb individual members of the structure within specified AISC tolerances. 3. Establish required leveling and plumbing measurements on the mean operating temperature of the structure. Make allowances for the difference between temperature at time of erection and the mean temperature at which the structure will be when completed and in service. 4. Splice members only where indicated on shop drawings. 5. Do not enlarge unfair holes in members by burning or by using pins. Ream holes that must be enlarged to admit bolts. 6. Installation of drilled-in expansion and injection adhesive bolts shall be performed in strict compliance with the manufacturer s recommendations for spacing and edge distances. Verify minimum thickness of base material for anchor used. E. Headed Studs: 1. Automatically end-weld headed studs in accordance with AWS D Surfaces to receive studs shall be free of foreign material such as rust, oil, grease, paint, etc. When mill scale is so thick as to prevent obtaining proper welds, remove by grinding or sandblasting. 3. Remove ceramic ferrules from studs and base material after welding. F. High-Strength Bolts: 1. Install and tension high-strength bolts according to the Research Council on Structural Connections Specification for Structural Joints Using ASTM A325 or A490 Bolts. 2. Bolts shall be A325 high-strength bolts, unless otherwise indicated. 3. Bolts shall be snug tight unless indicated as slip-critical, direct-tension or tensioned shear/bearing connections. G. Weld Connections: 1. Comply with AWS D1.1 for procedures, appearance, quality of welds and methods used for correcting welded work. 2. Comply with AISC specification referenced in this section for bearing, adequacy of temporary connections, alignment and removal of paint on adjacent surfaces. H. Erection Bolts: 1. On exposed welded construction, remove erection bolts, fill holes with plug welds, and grind smooth at exposed surfaces. 2. Comply with AISC Specifications for bearing, adequacy of temporary connections, alignment, and the removal of paint on surfaces adjacent to field welds. 3. Do not enlarge unfair holes in members by burning or by the use of drift pins, except in secondary bracing members. Ream holes that must be enlarged to admit bolts. I. Gas Cutting: Do not use gas-cutting torches in the field for correcting fabrication errors in the structural framing. Cutting shall be permitted only on secondary members that are not under URBAN PREP HIGH SCHOOL STRUCTURAL STEEL FRAMING

10 stress, as acceptable to the Architect. Finish gas-cut sections equal to a sheared appearance when permitted. 3.3 CLEANING A. Touchup Painting: Immediately after erection, clean field welds, bolted connections, and abraded areas of shop paint. Apply paint to exposed areas using same material as used for shop painting. 1. Apply by brush or spray to provide a minimum dry film thickness of 1.5 mils (0.038 mm). B. Galvanized Surfaces: Clean field welds, bolted connections, and abraded areas and apply galvanized repair paint according to ASTM A SUPPORT OF OTHER WORK A. No permanent loading, other than the weight of supported metal deck and concrete slabs, shall be imposed on floor and/or roof framing, until the concrete in such slabs has achieved 75 percent of its design strength. END OF SECTION URBAN PREP HIGH SCHOOL STRUCTURAL STEEL FRAMING