REVIEWING Shop Drawings by vvq21088

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									          REVIEWING
          Shop Drawings
                                                      Michael A. West, P.E.


  A leading engineer gives his approach to the shop drawing review process,
 based on standard AIA documents and the AISC Code of Standard Practice.

           he review and approval of         upon the Contractor’s submittals such as        review. Review of such submittals is not



T          shop drawings is a careful
           and methodical process.
           After “checking” structural
           steel shop drawings for
nearly 30 years, I have developed my
approach to the procedure, based on
the one that is described in the AIA
                                             Shop Drawings, Product Data and Sam-
                                             ples, but only for the limited purpose of
                                             checking for conformance with information
                                             given and the design concept expressed in
                                             the Contract documents. The Architect’s
                                             action will be taken with such reasonable
                                             promptness as to cause no delay in the
                                                                                             conducted for the purpose of determining
                                                                                             the accuracy and completeness of other de-
                                                                                             tails such as dimensions and quantities, or
                                                                                             for substantiating instructions for installa-
                                                                                             tion or performance of equipment or sys-
                                                                                             tems, all of which remain the responsibility
                                                                                             of the Contractor as required by the Con-
General Conditions of the Contract of Con-   Work or in the activities of the Owner,         tract documents. The Architect’s review of
struction as follows:                        Contractor or separate contractors, while       the Contractor’s submittals shall not re-
   “4.2.7: The Architect will review and     allowing sufficient time in the Architect’s     lieve the Contractor of the obligations
approve or take other appropriate action     professional judgment to permit adequate        under Paragraphs 3.3, 3.5 and 3.12. The
                                                                                             Architect’s review shall not constitute ap-
                                                                                             proval of safety precautions or, unless oth-
        Definitions from the AISC Code of Standard Practice                                  erwise specifically stated by the Architect,
                                                                                             of any construction means, methods, tech-
 Contract documents. The documents that define the responsibilities of the                   niques, sequences or procedures. The Ar-
 parties that are involved in bidding, fabricating and erecting structural steel.            chitect’s approval of a specific item shall not
 These documents normally include the design drawings, the specifications                    indicate approval of an assembly of which
 and the contract.                                                                           the item is a component.”
                                                                                                 Also, the AISC Code of Standard Prac-
 Design drawings. The graphic and pictorial portions of the contract docu-                   tice provides that shop-drawing review
 ments showing the design, location and dimensions of the work. These docu-                  is a “confirmation that the Fabricator has
 ments generally include plans, elevations, sections, details, schedules                     correctly interpreted the Contract docu-
 diagrams and notes.                                                                         ments in the preparation of the submit-
                                                                                             tals…”
 Embedment Drawings. Drawings that show the location and placement of                            In this context, the goal of the re-
 items that are installed to receive structural steel.                                       view is clear: to check for conformity
                                                                                             with the structural design as expressed
 Erection Bracing Drawings. Drawings that are prepared by the erector to il-                 in the contract documents. The pri-
 lustrate the sequence of erection, any requirements for temporary supports,                 mary way to ensure this is to establish
 and the requirements for raising, bolting and/or welding. These drawings are                that the detailer understands project re-
 in addition to the erection drawings.                                                       quirements and has applied them to
                                                                                             the shop and erection drawings in a
 Erection Drawings. Field-installation or member-placement drawings that                     clear and orderly way. Given this,
 are prepared by the fabricator to show the location and attachment of the in-               when I begin a review, my first activity
 dividual shipping pieces.                                                                   is to examine the submittal’s overall
                                                                                             appearance and content by paging
 Shop Drawings. Drawings of the individual structural-steel shipping pieces                  through it.
 to be produced in the fabrication shop.                                                         Next, I compare the erection plans
                                                                                             with the structural framing plans, eval-


                                                                                           March 2003 • Modern Steel Construction
uating member sizes, building-grid la-           Also, just as the detailer finds and re-       proved the Connection details shown
bels and dimensions, and top-of-steel            ports discrepancies in the contract doc-       on the Shop and Erection Drawing,”
elevations. I review the fieldwork de-           uments, the reviewer can find errors in        submitted in accordance with the re-
tails, and compare them to the struc-            the detailer’s work which are beyond           quirements of the contract documents.
tural drawings. I review any notes on            the reviewer’s scope. These discrepan-         The Code requires that the connections
the erection drawings as they relate to          cies are reported with the understand-         be fully designed in the contract docu-
the drawing notes and project specifi-           ing that the reviewer has not used this        ments; or, that information as to re-
cations. I also respond to any questions         depth of scrutiny throughout the re-           stricted connection types, and
that the detailer has written on the             view.                                          connection loads (shears, moments,
shop and erection drawings. Some de-                In reviewing the piece drawings, the        axial forces and transfer forces) is pro-
tailers (or project requirements) do not         beginning sheets are reviewed in               vided so the detailer can “select and
allow this form of question and re-              greater detail to establish a sense of the     complete” appropriate connection de-
sponse, but it is common on small- to            detailer’s approach to the job and the         tails. To satisfy this requirement the re-
intermediate-size projects. Usually the          detailer’s grasp of the construction           viewer might have to make some
next drawings to be reviewed are the             document’s requirements. The follow-           shorthand calculations to determine if
embedment plans and associated piece             ing is a list of items that must be re-        the project requirements have been
drawings. These are reviewed against             viewed in detail:                              met. Since the approaches given in the
the design drawings for such things as           I Member size and material specifica-          Code of Standard Practice limit the de-
anchor rod diameters, other anchor di-              tion                                        tailer to AISC-tabulated connections,
ameters, materials, arrangements and             I Piece mark, plan location and base           the process of confirming that the de-
embedments. Since embedded material                 length                                      tailer understands the loads and tabu-
falls outside the scope of the typical de-       I Camber, if any                               lated connection resistances should
tailer’s requirement to “develop” con-           I Surface preparation and coating, if          only take a few in-depth reviews. How-
nections, deviations from the contract              any                                         ever, the reviewer should be alert to
documents are rare, but this must be             I Connections                                  special conditions, such as deep copes
established in the review.                          •Geometry and layout                        or top and bottom copes, that could af-
    Lastly, the review of the shop draw-            •Bolt sizes, type and material speci-       fect connection strength. The shop
ings for the individual shipping pieces               fication                                  drawing review process also allows the
begins. As the Code of Standard Practice            •Hole sizes, types                          reviewer to reconfirm that the connec-
states, the detailer’s responsibility is            •Masking for SC-type connections            tion requirements specified are appro-
“The transfer of information from the con-          •Weld geometry, fillet size and             priate for the piece in question.
tract documents into accurate and complete            length, PJP and CJP                           Lastly, any corrections must be
Shop and Erection Drawings; and, the de-            •Connection types                           transferred to all of the submitted
velopment of accurate, detailed dimen-              •Connection material specifications         copies. This is not an idle activity. It
sional information to provide for the fit-up        •Copes and edge distances                   gives the reviewer another chance to
of parts in the field.” Just as the fabricator      •Bolt and weld material strengths,          look through the entire submittal. Per
is not required to discover errors or dis-            specifications                            the Code of Standard Practice, each sheet
crepancies in the contract documents, it         I Stiffeners                                   must be individually marked with its
is not the reviewer’s responsibility to          I Openings for other trades                    disposition. #
find errors or discrepancies in the de-             The Code of Standard Practice re-
tailer’s work beyond what is appropri-           quires that the EOR’s review of the               Michael A. West, P.E. is vice-president
ate to the goal of establishing                  Shop Drawings provides confirmation            and a principal of Computerized Structural
conformity to the contract documents.            that the EOR has “reviewed and ap-             Design, S.C., in Milwaukee, WI.




                                                                                              March 2003 • Modern Steel Construction

								
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