Marcas en conflicto con dos o más DOP/IGP

The metal building industry has pioneered the use of one-sided web to flange welding techniques. The use of one-sided welds are permissible in both the AISC and AWS Specifications, but proper controls on the welding techniques are required to make sure the joint is properly executed.

The web to flange welds in metal buildings are typically not loaded in tension but are primarily loaded in shear. This permits the use of one-sided fillet welds without concerns of rotation about the longitudinal axis of the weld. However, if the fillet weld is subject to loads that impart significant rotation, stiffeners or other means should be used to preclude this rotational loading on the weld.

4.2.3.1.2 Background

Automatic welding equipment revolutionized the shop fabrication of large steel members during the middle of the 20th century. The development of pull-through automatic welding machines, where the member component web and flanges are pulled past welding nozzles, has greatly contributed to the use of steel in building construction. Economic use of steel for large clear span frames was the initial driving force in the use of welded, web tapered members. Advanced technology in the form of the pull-through automatic welding machine utilizing one-sided welding has led to the general use of prismatic and web tapered members for all types of rigid frame and braced frame applications. This method of steel member fabrication was specifically included in the original AISC MB Certification program and is part of the IAS AC472 Accreditation program.

4.2.3.1.3 Testing

The metal building industry has sponsored research involving a large number of tests of rigid frame components. The great majority of these tests were conducted using built-up beams and columns with one-side web-to-flange welds. Dr. Joseph Yura, Professor Emeritus, University of Texas, conducted tests to evaluate the ultimate strength of welded slender-web girders, the interaction of web buckling, local flange buckling and lateral buckling. In this test program, thirty girders (24-foot long) were tested to maximum load and beyond to produce very severe buckling deformations. The girders had five different web depths and two different flange thicknesses. All the girders were

fabricated with a one-sided fillet weld connecting the web plate to the two flange plates using an automatic submerged - arc process following AWS D1.1 procedures. The beams were loaded into the inelastic range of behavior. All the test beams ultimately failed by lateral buckling, local flange buckling or web buckling. The local flange buckling failures, in particular applied a severe loading condition to the one-sided weld but the tests resulted in no change in the 90 degree angle between the flange and the web plates. The one-sided welds ultimately performed very well with no weld failures (Ref. B7.18).

A deviation from the general pattern of the acceptability of one-sided fillet welds occurs when seismic detailing of end plate connections is required for intermediate moment frames. AISC CPRP 6.4(1) requires that two sided fillet welds, or CJP groove weld, be provided for the web to flange connection for a distance from the end plate of at least the depth of the web, or three times the width of the flange (Ref. B7.19).

Page 351, Section 1.3 References, Revise the following references to read as follows:

A. AISI – North American Specification for the Design of Cold-Formed Steel Structural Members, including 2004 Supplement 2007.

B. AISC 360 - Specification for Structural Steel Buildings, 2005.

C. AISC - Steel Design Guide Series 3 - Serviceability Design Considerations for Low-Rise Buildings, Second Edition, 2003.

D. ANSI/ASHRAE/IESNA Standard 90.1 – 20042007 - Energy Standard for Buildings Except Low-Rise Residential Buildings.

E. ASTM A36-0408 - Specification for Carbon Structural Steel.

F. ASTM A123-0208 - Specification for Zinc (Hot-Dip Galvanized) Coatings on Iron and Steel Products.

G. ASTM A153-0405 - Specification for Zinc Coating (Hot Dip) on Iron and steel Hardware. H. ASTM A307-04b07b - Specification for Carbon Steel Bolts and Studs, 60,000 psi Tensile

Strength.

I. ASTM A325-04b 09 - Specification for Structural Bolts, Steel, Heat Treated, 120/105 ksi Minimum Tensile Strength.

J. ASTM A463-0206 - Specification for Steel Sheet, Aluminum-Coated, by the Hot-Dip Process. K. ASTM A475-03 - Specification for Zinc-Coated Steel Wire Strand.

L. ASTM A490-04b08b - Specification for Heat Treated Steel Structural Bolts, 150 ksi Minimum Tensile Strength.

M. ASTM A500-03a 07 - Cold-Formed Welded and Seamless Carbon Steel Structural Tubing in Rounds and Shapes.

N. ASTM A501-0107 - Specification for Hot-Formed Welded and Seamless Carbon Steel Structural Tubing.

O. ASTM A529-0405 - Specification for High-Strength Carbon-Manganese Steel of Structural Quality.

P. ASTM A572-0407 - Specification for High-Strength Low-Alloy Columbium-Vanadium Structural Steel.

Q. ASTM A653-04a08 - Specification for Steel Sheet, Zinc-Coated (Galvanized) or Zinc-Iron Alloy-Coated (Galvanized) by the Hot-Dip Process.

R. ASTM A792-0308 - Specification for Steel Sheet, 55% Aluminum-Zinc Alloy-Coated by the 37

Hot-Dip Process.

S. ASTM A1011-04a08 - Specification for Steel Sheet and Strip Hot Rolled Carbon, Structural High Strength Low-Alloy and High Strength Low-Alloy with Improved Formability.

T. ASTM C665-0106 - Specification for Mineral-Fiber Blanket Thermal Insulation for Light Frame Construction and Manufactured Housing.

U. ASTM D1494-97(20012008) - Test Method for Diffused Light Transmission Factor of Reinforced Plastic panels.

V. ASTM E1514-98(2003) - Specification for Structural Standing Seam Steel Roof Panel Systems. W. ASTM E1592-01 - Test method for Structural Performance of Sheet Metal Roof and Siding

Systems by Uniform Static Air Pressure Difference.

X. ASTM E1646-95(2003) - Test Method for Water Penetration of Exterior Metal Roof Panel Systems by Uniform Static Air Pressure Difference.

Y. ASTM E1680-95(2003) - Test Method of Rate of Air Leakage through Exterior metal Roof Panel Systems.

Z. AWS A2.4 - Standard Welding Symbols, 1998.

AA. AWS D1.1 - Structural Welding Code - Steel, 2000 2008. AB. AWS D1.3 - Structural Welding Code - Sheet Steel, 1998.

AC. MBMA Metal Building Systems Manual, 2006 with 2010 Supplement.

AD. NAIMA 202 - Standard for Flexible Fiberglass Insulation Systems in Metal Buildings, 2000. AE. SJI (Steel Joist Institute) - Standard Specifications, Load Tables and Weight Tables for Steel

Joists and Joist Girders, 41st42nd Edition.

AF. SSPC (Society for Protective Coatings) - SP-2 - Specification for Hand Tool Cleaning, 2004 (Part of Steel Structures Painting Manual, Vol. Two)

AG. SSPC - Paint 15 – Steel Joist Shop Primer/Metal Building Primer; Society for Protective Coatings; 2004 (Part of Steel Structures Painting Manual, Vol. Two)

AH. SSPC – Paint 20 – Zinc-Rich Primers (Type I, “Inorganic”, and Type II, “Organic”); Society for Protective Coatings; 1991 (Part of Steel Structures Painting Manual, Vol. Two).

AI. UL 580 - Tests for Uplift Resistance of Roof Assemblies, 19942006.

Page 356, Section 1.7 – Qualifications, revise text to read as follows:

A. Manufacturer: The company manufacturing the products specified in this Section [shall have a minimum of [ ] year[s] experience in the manufacture of steel building systems.] The Manufacturing company shall be certified under the American Institute of Steel Construction’s Category MB Certifications Program. The metal building systems manufacturer shall be accredited under the International Accreditation Service, Inc., “Accreditation Criteria for Inspection Programs for Manufacturers of Metal Building Systems (AC472)”.

Page 367, Chapter VI – AISC-MB Certification Program, revise title to read as follows:

VI. AISC-MB Certification Program IAS Metal Building Manufacturers Accreditation Program

Page 367, Section 6.1 – Introduction, revise text to read as follows:

The interpretation of the design analysis and the determination of the quality of the end product may be beyond the capability of end users, system specifiers, and building inspectors. If so, they must rely

upon the integrity and reputation of the manufacturer or a third party opinion such as an independent certification accreditation agency.

The American Institute of Steel Construction (AISC) Metal Building Certification International Accreditation Service, Inc. (IAS) Inspection Programs for Manufacturers of Metal Building Systems, (AC472) fills this need. International Accreditation Service accredits testing and calibration laboratories, inspection agencies, building departments, fabricator inspection programs and IBC special inspection agencies. A recognized accreditation body since 1975, IAS is a nonprofit, public benefit corporation. IAS is one of the leading accreditation bodies in the United States and a signatory to several international mutual recognition arrangements (MRAs).

The Program examines and certifies accredits the in-place capability of a metal building manufacturer's organization and facilities to meet and, on an ongoing basis, to adhere to the AC472 Program Criteria requirements regarding administrative policies, procedures, and personnel qualifications, design policies, procedures and practices, material procurement, product traceability, and manufacturing and quality assurance control procedures and practices. In fact, the AISC-MB Certification The AC472 Program is the most a comprehensive quality certification accreditation program of its kind based on the requirements of Chapter 17 of the International Building Code. Unlike other accreditation and certification programs, the AISC-MB AC472 program is the only one that includes engineering design. This is verified by IAS and an IAS-accredited a third-party inspection agency on-site inspection to that confirms that the appropriate standards are in place and being applied in actual projects.

The ultimate responsibility for the integrity of a metal building system rests with the manufacturer and project design professionals. AISC IAS does not accredit, certify or warrant the performance of any specific metal building system.

Page 367, Section 6.2 – Objectives, revise text to read as follows:

The objectives of the AISC IAS AC472 Metal Building Accreditation Certification Program are:

1) To provide a uniform, nationally recognized, certification accreditation program for metal building systems manufacturers that incorporate engineering services, fabrication and shop practices as an integral part of the fabricated end product.

2) To evaluate the basic design and quality assurance procedures and practices used by a manufacturer with regard to the organization's capability to produce metal building systems of predictable structural integrity and quality that can meet public safety requirements imposed by the applicable building code.

3) To certify accredit manufacturers that have submitted to a rigorous examination of their professional engineering and manufacturing policies, procedures and practices and their quality assurance standards and controls and have been found to meet predictable structural integrity and quality that can meet public safety requirements obligatory by the applicable code and set forth in the Program.

4) To periodically audit certified accredited manufacturers for continued compliance with Program requirements.

5) To aid, assist and encourage non-accredited manufacturers and the various code authorities to adopt the Program in order to improve the integrity of design and quality of fabrication within the metal building systems industry for the benefits of the consumer.

Page 368, Section 6.3 – Benefits, revise text to read as follows:

The central benefit that Customers, Specifiers, Contractors, Code Officials and Building Owners gain from working with AISC-MB Certified AC472 accredited metal building manufacturers is that they can rely on the quality of the finished product in terms of engineering and manufacturing. Some of the other benefits of AISC-MB Certification AC472 Accreditation are:

1) Accredited manufacturers employ experienced licensed professional engineers who have responsible charge over the design and detailing of the metal building system.

1) 2) Certified Accredited manufacturers have undergone rigorous third-party examination of their professional engineering and manufacturing policies, procedures and practices.

2) 3) Quality assurance standards and controls have been found to meet the requirements established in the certification accreditation program.

3) 4) Annual Semi-annual on-site audits by IAS and its Accredited Inspection Agencies ensure continued compliance with the program requirements.

4) 5) Certified Accredited manufacturers have proved under the program that they can meet the public safety requirements imposed by the applicable building codes because their basic design and quality assurance procedures and practices used to produce metal building systems meet the needs of predictable structural integrity and quality.

5) 6) This program enables local, national and international code groups to utilize an already established and nationally recognized certification accreditation agency to verify compliance with their standards.

More specific benefits for the involved parties are categorized below: Specifiers:

• By requiring certification accreditation, the specifier can easily disqualify suppliers who cannot pass the stringent audit requirements of AISC-MB Certification AC472 Accreditation.

• Specifying an AISC-MB Certified AC472 accredited company provides the specifier with the opportunity to say that quality is important to them and to their project.

• Since the specifier is not doing the structural design, certification accreditation assures that engineers who have demonstrated knowledge of building systems and applicable codes are designing the product.

Contractors:

• Allowing Using only certified accredited suppliers helps protect the contractor’s good name by guaranteeing that a committed, audited supplier is on the project.

• Certification Accreditation requires that the manufacturer use raw materials that comply with applicable specifications.

• Certification Accreditation requires that erection drawings are clearly written and show all appropriate information for the proper erection of the building.

Code Officials:

• The Program is based on the requirements of Chapter 17 of the International Building Code. 40

• Allowing Using certified accredited suppliers helps achieve the code official’s goal of guaranteeing that a properly-vetted building supplier is on the project.

• Certification Accreditation requires that all Letters of Certification, Design Calculations and Drawings be clearly communicated and stamped by a fully qualified design professional.

Building Owners:

• Better Protection for occupants and contents • Lower insurance rates

• Lower maintenance costs • Lower utility costs • Better resale value

Up-to-date information and news releases regarding the AISC-MB Certification AC472 Accreditation Program can be found at www.mbma.com and www.iasonline.org. The Inspection Programs for Manufacturers of Metal Building Systems, (AC472), Criteria can also be downloaded directly from the IAS website at www.iasonline.org. The Procedures for Certification, Evaluation Criteria, and Application Forms can be downloaded directly from AISC’s website: www.aisc.org.

Page 370, Section 7.1 - General, revise text to read as follows:

Energy conservation is an important consideration for building owners and designers that is regulated through local and national codes. These energy codes are evolving, becoming more stringent, and being better enforced. Understanding energy conservation requires a basic understanding of the theory, terms, and construction practices to obtain an energy efficient building. Good planning and proper use of energy conservation principles will pay off in long-term economic gains for the owner, comfort for the occupants, and reductions in maintenance and modification to the building as it ages.

The MBMA has published the Energy Design Guide for Metal Building Systems (Ref. B9.11) to aid building owners, architects, specifiers, contractors, builders, and metal building manufacturers in their efforts of building energy conservation. The Energy Design Guide is a synthesis of all of the pertinent information on how to design, construct, and maintain metal buildings to be energy efficient. The

Energy Design Guide for Metal Buildings Systems replaces the information that was previously in this

section in the previous MBMA Metal Building Systems Manual.

To obtain a copy of the MBMA Energy Design Guide for Metal Building Systems go to

http://www.mbma.com for more information.

The table of contents of the Energy Design Guide for Metal Building Systems is shown below (without underlines):

Chapter 1 Introduction

• Green Building and Sustainable Construction

o Benefits of Conservation and Energy Efficiency o Emissions

• Potential Energy Savings o Regulations o Efficient Design o Life Cycle Assessment