How to Improve your Shop Drawing Review By Michael Gustafson, P.E. April 2013 How to Improve your Shop Drawing Review By Michael Gustafson, P.E. he structural steel detailing industry has contin- A signed set of calculation sheets from a professional engineer ued to expand its use of 3D modeling technology for all connection designs not covered by the design drawing contract in recent years; currently more than 80 percent of the structural steel detailing market in the the COSP states that the SEOR shall review and approve structural TUnited States is using some form of 3D/BIM modeling software (American Institute of Steel Construction, 2011). This change has brought great to the steel detailer’s Continuing Education own productivity, in addition to improving upstream and If you read the following article, display your downstream processes. The Structural engineer, however, understanding of the stated learning objectives, and has not adopted 3D models to improve their own productivity in reviewing and approving structural steel of your continuing education requirements at no cost shop drawings. According to the same fabricators using 3D to you. modeling above, less than 1% use these models in the Instructions review process with the structural engineer. Comparatively 70% First, review the learning objectives below, then of structural engineers have adopted 3D models/BIM for design read the Professional Development article. Next, coordination and drawing production. So why hasn’t this adoption complete the quiz and submit your answers to the of design review trickled into shop drawing review? Professional Development sponsor. Submittal AISC’s survey outlines several barriers that include perceived instructions are provided on the Reporting Form software learning and costs, liability issues reviewing the model, on page 6. Your quiz answers will be graded by the and paper-based contract requirements. Despite these barriers, the structural engineering industry looks positive towards shop Professional Development sponsor. If you answer model review. AISC’s survey states that 60% structural engineers at least 80 percent of the questions correctly, you will see model-based review of shop drawings being an industry of completion within 90 days and will be awarded 1.0 professional development hour (equivalent to 0.1 continuing education unit in most drawings using a range of emerging technologies. The transfer of states). Note: It is the responsibility of the license to digital technology, but now enhanced visualization methods of determine if this method of continuing education meets review have been implemented on several projects around his or her governing board(s) of registration requirements. the country. What is the SEOR’s scope for Learning Objectives sho p drawing review? The learning objectives of this paper are the following: • Understand current contractual and industry- Per AISC’s survey to structural engineers in 2011, structural expected responsibilities of the engineer-of-record in the shop drawing review process. project during the construction administration phase. In this phase, • Identify ineciencies or redundancies in the current the tasks of reviewing and approving shop drawings still prove to be review processes. while the importance of the task remains as important as ever. • Learn how 3D visualization tools can be used to coor- The American Institute of Steel Construction (AISC) Code of dinate, review, and approve shop drawing submittals Standard Practice (COSP) outlines what is required of the steel while still delivering a 2D submittal of shop drawings. fabricator and of the SEOR in the submission and approval of shop • Comprehend industry trends moving toward a 3D drawings. Minimal information is provided regarding the content to model-based shop drawing review process. be reviewed by the SEOR, since this is typically outlined at the Professional Development Sponsor TEKLA Inc. The COSP states that a steel fabricator expects a 14 calendar-day turn around from the day it releases drawings to the day the fabricator receives the approved shop drawings back from the With the nature of today’s accelerated project delivery schedules, a two-week turn around time of shop drawings is not the norm, thereby putting more stress on the review team to be more productive and turn around approved submittals in less time. 2 PDH How to Improve your Shop Drawing Review connections and details designed by others drawings. All the industry leading steel detailing- (see COSP – Section 4.4.1). The submittal of connection software packages provide some type of free viewer Standards for shop drawing review The SEOR has an obligation to verify that the structural design of the SEOR approving 2D paper drawings, but the process intent is being properly communicated by the steel fabricator how this is conducted are determined by the SEOR or, more containing the approval comments by the EOR. In other words, commonly, by a company standard. Typically, structural the use of the 3D model is to make the review process more engineers will follow a checklist for reviewing and approving the erection and assembly shop drawings. 2D paper approval drawings. Key steps the steps in the detail needs to go into checking shop drawings. Typically, the Step 1. Coordination of building systems structural assemblies — comprised of primary framing and connection parts — are reviewed for compliance at three levels: between the structural systems (such as structural steel, cast-in-place concrete, within the context of other building systems, within the context- precast, etc.) that have surfaced during the shop drawing stage that ultimately of other structural assemblies and structural systems; and within their own structural assembly. Furthermore, for each level of by means and methods (which is typically not part of the SEOR’s scope of work), investigation, several design parameters are typically reviewed such as geometry, section properties, amnd aterial properties. the 3D construction model, which has a much higher level of detail, can be Checking each of these parameters can be a tedious process. appropriate. In addition, the task of reviewing each checklist item on the To coordinate interfaces of the structural steel frame with other structural shop drawings and comparing that information with the design elements such as concrete foundations and walls or roof joists, structural engineers can import their 2D design drawings or 3D structural models, fabricator’s 3D model (also referred to as the construction model) including building information models (BIMs), into the construction model. can help the SEOR better visualize and review the shop drawings The overlaying reference can be used to verify the steel structure geometry as as well as speed up the SEOR’s time reviewing the shop drawings. well as clearances and tolerances (see Figure 1). The geometry of the model elements can be reviewed in interactive reports that can be created within the construction model, or from the model elements For more than 80 percent of the projects built in the United States that detail structural steel (AISC, 2011), the SEOR may context of the construction model is that the contents of both are superimposed obtain access to the 3D construction model for review of together in one location. This eliminates the SEOR’s need to go back and forth shop drawing submittals. Such tools can be helpful in between design plans and the fabricator’s erection drawings. improving th e SEOR’s understanding of the proposed To coordinate the structural steel frame with non-structural elements such as fabricated product by the steel fabricator. Several overlay either 2D drawings or 3D reference models into the steel construction 3D construction model in the review process. These model. visualization tool — which still requires 2D shop drawings fabricator — to the approval of the 3D construction model in lieu of 2D drawings. of 2D design drawings and the 3D steel construction model. that utilize everything from 2D paper to 100% model review (Gustafson 2007; Quinn 2009; Moor 2012). In this paper, Model-Assist, Hybrid Review, and Model Review Lite. Model-Assist Model-Assist basically represents the traditional shop drawing approval process in which the structural engineer’s design drawings are used along with the fabricator’s submitted shop drawing set but with the aid of the fabricator’s 3D model. Especially for complex framing conditions, the ability to visualize the shop assemblies in 3D is a great asset to the structural engineer and can greatly improve the quality of review, even if the formality of the review is still done with traditional PDH 3 How to Improve your Shop Drawing Review Step 2. Review and approval of assemblies — As described above, enhanced visualization tools exist to help the EOR better understand how their design intent is being interpreted by the builders. With this in mind, there are opportunities to improve the actual review process itself are successfully reviewing 2D drawings electronically using coordinating of information between the design and shop drawings. For example, the SEOR can spend a fair amount of time An example of an reviewed and stamped assembly shown in both assembly sheet that they wish to review. In contrast, the the 3D model and 2D electronic drawings in PDF format. model, and then open the corresponding, 2D electronic During connection design approval process, the SEOR can also utilize the shop drawing to view the assembly as needed. Secondly,