From:
AWS D1.8/D1.8M:2009 Structural Welding Code - Seismic Supplement1.2 Responsibilities
1.2.1 Engineers ResponsibilitiesIn addition to the items listed in AWS D1.1/D1.1M, the engineer shall provide the following information in the contract Documents:
(1) Connection Configuration, Material Specifications, and part sizes required to provide the needed seismic performance
(See 1.3).
(2) Identification of member that comprise the Seismic Force Resisting System (SFRS) and that are subject to the provisions of this code (See 3.1).
(3) The location of the Protected Zone for members of the SFRS
(See 3.3).
(4) Welds designated as Demand Critical and subject to specific provisions of this code
(See 3.2)And continues to describe requirements for various location situations from (5) thru (9).
(10) Lowest Anticipated Service Temperature (LAST) of the steel structure for structures not normally enclosed and maintained at a temperature of 50F(10C) or higher
(See 3.5 & 6.3.6).
(11) Butt joints subject to tension where tapered transitions are required
(See 4.2).
(12) Those joints or groups of joints in which a specific assembly order, welding sequence, welding technique or other special precautions are required (See AWS D1.1/D1.1M subclauses 2.23 and 5.21).
(13) Quality Assurance Plan for the Project
(see 3.4 & 7.1).
(14) Any Additional provisions applicable to the specific project NOT governed by AWS D1.1/D1.1M or this code.
3. Terms and Definitions
3.1 Seismic Force Resisting System (SFRS):The assembly of structural elements in the building that resist seismic loads, as indicated by the Engineer in the Contract Documents. Included in the SFRS are columns, beams, girders and braces, and the connections between these elements specifically designed to resist seismic loads, either alone or in combination with other loads. The SFRS does NOT include other structural member Not designed to resist seismic loads. Straining is anticipated to occur and to which special limitations in these provisions apply with regard to attachments and fabrication.
3.2 Demand Critical WeldsWelds designated by the Engineer in the Contract Documents, and required to meet the specific requirements of this code
3.3 Protected Zone:That portion of a member of the SFRS, designated by the Engineer in Contract Documents in which inelastic straining is anticipated to occur and to which special limitations in these provisions apply with regard to attachments and fabrication.
3.4 Quality Assurance Plan (QAP)The written descriptions of qualifications, procedures, quality inspections, resources and records to be used to provide assurance that the structure complies with the Engineers quality requirements, specifications, jurisdictional requirements, and Contract Documents.
6. Fabrication
6.6 Tack Welds to steel backing in the Protected Zone.Tack welds between backing and beam flange outside the weld joint shall be prohibited. Tack welds that attach steel backing to groove welds in the Protected Zone shall be placed within the weld joint, when practicable with the following exception: Steel backing may be tack welded to columns for beam to column welds.
6.11 Weld Tabs
6.11.2 Tack Welds attaching Weld Tabs. tack welds attaching weld tabs in the Protected Zone shall be made within the joint, and shall meet the requirements of
6.16. Then there's
6.12, 6.13, 6.14.6.15 Protected Zone
6.15.1 Attachments and Welds. Welded attachments, including stud welds and fasteners for the connection of other materials, shall be prohibited within the Protected Zone.
arc spot welds (Puddle Welds) for the attachment of metal decking shall be permitted in the Protected Zone.
6.15.2 Erection Aids. If erection aids are required to be attached within the Protected Zone, the Contractor shall obtain the Engineers approval for use of such attachments.
6.15.3 Removal of welds in the Protected Zone. 6.15.4 Repair of Gouges and Notches. Gouges and Notches in the Protected Zone shall be repaired as follows:
6.15.4.1 Grinding When gouges and notches are repaired by grinding, the ground area shall provide a gradual taper to the surface of the base metal. In the direction parallel to the member axis, taper shall Not be greater than 1:5. In the direction transverse to the member axis, the taper shall NOT be greater than 1:2.5.
6.15.4.2 Repair Welding of Gouges and Notches. When repairs require welding, the notch or the gouge shall be removed to provide a smooth radius of not less than 1/4 in[6mm] in preparation of welding.Welding shall be done in accordance(to) an applicable WPS. Preheat shall be in accordance to AWS D1.1/D1.1M, but shall not be less than 150F[65C]. Electrodes shall comply with 6.3. Following welding, the repair weld shall be ground to a smooth contour with a surface roughness not to exceed 500uin[13um].
AWS C4.1. Criteria for Describing Oxygen Cut Surfaces, and Oxygen Cutting Roughness Gauge, Sample 4, may be used as a guide for evaluating surface roughness of these surfaces. After repair, the area shall be inspected using Magnetic Particle Testing (MT). The resultant thickness of the repaired area shall be no less than the base metal thickness less 1/16 in.[1.5mm].
6.16 Tack Welding Requirements6.16.2 Placement of Tack Welds. In the Protected Zone, unless specifically required or permitted by the Engineer, and shown on detail drawings, tack welds shall be prohibited outside the weld joint. 6.16.3 is pretty much self explanatory with any gouges or notches to repaired according to
5.15.4.
7 Inspection
7.1 Inspection Task Assignment. When required by the Applicable Building Code or Contract Documents, the Engineer shall prepare a Quality Assurance Plan (QAP). The Quality Assurance Plan shall identify the specific Quality Control and Quality Assurance tasks to be performed on the project respectively by the Contractor and the Quality Assurance (QA( Agency. The Contractor and the Quality Assurance Agency shall perform those tasks as identified in the Quality Assurance Plan.
Then we jump ahead to
7.6 & 7.7.
7.6 Beam Copes and Weld Access Holes When required by the QAP, beam copes and weld access holes shall be inspected for cracks on the cut surface prior to welding.
Inspection shall be performed using Magnetic Particle Testing (MT) or Dye Penetrant Testing (PT).
7.7 Repaired Weld Access Holes in the Protected ZoneInspection of repairs to a weld access hole in the Protected Zone, shall be by Magnetic Particle Testing (MT) or Dye Penetrant Testing (PT).
Commentary on Structural Welding Code - Seismic SupplementThis commentary will enlighten anyone who is still struggling with the clauses in the code regarding the Protected Zone as well as many other factors... This Commentary on AWS D1.8/D1.8M:2009 has been prepared to generate better understanding in the application of the code to welded construction of steel in seismic applications. Since the code is written in the form of a specification, it cannot present background material, or discuss the Structural Committee's intent; it is the function of this commentary to fill this need.
So it basically covers the same topics as in the clauses of the code but, much more in depth and details to give the reader some clarification of the what, how, and why that some of us can misunderstand, or be left unsatisfied with the meaning of the clauses as they are written in the form of specifications... Imagine if we only depended on the clauses in the code only and totally disregarding the commentaries and annexes? Talk about confusion!
I am going to go past C1 General Requirements but you don't have to, and ask all of you to take a good look @ the tables and the figures found in C1 and observe the table:
C1.1 Removal of Tabs and Backing The table is pretty much self explanatory and yet as it is written previously if in doubt, one should give the engineer an RFI (Request For Information) to clarify what the engineer wants to be done because they, and only they have the authority to make whatever decision to go with in the contract documents since they write the provisions in the contract documents in the first place... If you then look @ Figures C1.1 to C1.3, you will notice the different examples of where the protected zones are, SFRS members, Demand Critical Welds, and joints subject to the requirements of D1.8 yet aren't commonly known demand critical welds as well as D1.1 joints that are subject to the requirements of D1.1 only... Where they are located with respect to each connection, and all three figures refer to C1.2.1, items 2,3, and 4 of the commentary.
I could go on but, I know that it's best for me to stop here regarding the D1.8 Seismic Supplement... Besides, if you can get into the AWS website, you can find a gem of an article in this summer's "Inspection Trends" titled" Understanding Protected Zones" by Brent E. Boling - Here are answers to whether you can or can't perform welding in the "Protected Zone". that pretty much covers this code supplement more so in some of the applicable real world perspectives than what I just posted... Here's a link or two for the article I just mentioned:
http://www.aws.org/itrends/current.htmlhttp://www.nxtbook.com/nxtbooks/aws/it_201407/Here's an interesting read that ought to spark a discussion on this very subject...it's a Technical Bulletin from the Metal Building Manufacturers Association published Winter 2008;
http://www.mbma.com/pdf/Welding%20Issues%20-%20Winter%2020081.pdfAnother good article from "Steel Wise" MODERN STEEL CONSTRUCTION, October 2008 regarding AWS D1.8., FEMA 350 thru 353 & FEMA 2000d, the AISC documents and some history as well:
http://www.modernsteel.com/Uploads/Issues/October_2008/102008_steelwise_web.pdfAn article written for the February 2007 edition of the AWS Welding Journal titled: "New AWS D1.8 Seismic Welding Supplement Outlined"
BY RONALD O. HAMBURGER (NOT Ronald McDonald
), JAMES O. MALLEY, AND DUANE K. MILLER:
http://www.aws.org/www/wj/2007/02/WJ_2007_02.pdfFinally, this is a very good overview of AWS D1.8 from Lincoln Electric: D1.8 Seismic Supplement Welding Manual
A General Overview of AWS D1.8 Structural Welding Code - Seismic Supplement:
http://www.lincolnelectric.com/assets/US/EN/literature/C165.pdfThis is Lincoln Electric's AWS D1.8 Resource Center webpage which is mostly advertisement for which I do apologize:
http://66.181.85.219/D1.8.aspAs you all know by now - I could go on but, I'll just stop before someone catches an attitude because of all of the information I tend to "stuff" into my posts... Sheesh!!!
So enjoy and I hope this is helpful.
Respectfully,
Henry