BIM enhances structural analysis regardless of project size By Doug Fitzpatrick, P.E., LEED AP and Jeffrey Yoders MARCH 2013
BIM enhances structural analysis regardless of project size By Jeffrey Yoders The owner of a major rehabilitation center project required Building Information Modeling as a way to help it manage its facilities as well as to reduce design and construction change orders. After several pilot projects, this owner a major healthcare provider in the Southeast with a significant portfolio of assets determined BIM would be highly beneficial and saw measureable savings before and during construction of the new facility. It was designed in late 2011 and completed in early 2012. The Rehabilitation Center project, a two-story, 65,000-squarefoot, steel-framed building designed for a future floor, was the owner s first IPD-lite project, with the design team, contractor and major subcontractors all on board as a highly collaborative team from the first meeting. While the team was integrated, traditional contracts were used for the roles of design architect, general contractor and structural engineer. Although the project was constructed with a traditional paper delivery, the owner required a 2012 Revit model deliverable from all design disciplines, including framing plans, and expected the structural engineer, Fitzpatrick Engineering Group of Cornelius, N.C., to share their design model data with the steel fabricator, SteelFab of Charlotte, N.C. The combination of a Revit deliverable and sharing the engineer s model data with the fabricator presented a particular challenge for Fitzpatrick. Sharing structural model information with downstream members of the construction team has been a core component of FEG since we completed our first BIM project in December 2006 and successfully shared our model data with the fabricator, said Doug Fitzpatrick, managing partner of FEG. This fully detailed structural model of the Rehabilitation Center was passed on to the general contractor after design. Instructions The Professional Development Series is a unique opportunity to earn continuing education credit at no cost to you by reading specially focused, sponsored articles. After reviewing the learning objectives below, read the Professional Development Series article and complete the quiz online at http:// continuingeducation.zweigwhite.com. Quiz answers will be graded automatically and, if you answer at least 80 percent of the questions correctly, you can immediately download a certificate of completion and will be awarded 1.0 professional development hour (equivalent to 0.1 continuing education unit in most states). Note: ZweigWhite is an Approved Provider by the American Institute of Architects Continuing Education System (AIA/CES). However, it is the responsibility of the licensee to determine if this method of continuing education meets his or her governing board(s) of registration s requirements. Learning Objectives After reading this article you should be able to: tor with a model ments Professional Development Series Sponsor Bentley Systems, Incorporated 2 PDH Professional Development Advertising Section Bentley Systems, Incorporated
Though not all of our projects require collaboration, we create all of our models as if we would be sharing data with a fabricator. In the beginning of the Rehabilitation Center project, in fall of 2011, FEG performed an internal study of the ability of AECOsim and Revit to share information with a steel fabricator via the CIMSteel Integration Standards (CIS/2 file). FEG examined what information was exported from each BIM platform as well as what information was imported into was the winner with model accuracy and the most amount of structural information exported. The Revit CIS/2 export only supported member sizes requiring the detailer to reenter a significant amount of design data and did not accurately export member geometry. It was obvious AECOsim would be the basis for FEG s design model to satisfy the owner s request to share model data downstream, but FEG still needed to provide the owner with a Revit model at project closeout. Getting information out the way everyone wanted it to be sent was challenging, Fitzpatrick said. We had to use Revit, but also had to hand off good information to the fabricator. To solve its information problem, FEG turned to Structural Synchronizer s Integrated Structural Modeler (ISM). ISM is a repository of structural information that can be used to share data and manage changes between ISM-enabled programs such as RAM Structural System V8i. AECOsim uses the Structural Synchronizer to communicate with the database. The structural group at Bentley has also developed an ISM plug-in for Revit. These two tools were critical in allowing FEG s engineers to satisfy both owner constraints share accurate data with the fabricator and provide a Revit deliverable. We could work in our preferred BIM application, confident in being able to send reliable information to the fabricator and deliver a Revit model through electronic means without having to manage two models separately, Fitzpatrick said. FEG s team ran into a snag when the ISM plug-in was only available for Revit 2011 during the design phase of the project, not the required Revit 2012 deliverable. To complicate the situation further, the then-current version of ISM did not support transferring enough data from AECOsim to Revit 2011 via the ISM to provide an appropriate level of detail for framing plans in Revit. Through a combination of electronic transfers using the RAM->Revit and RAM->AECOsim link, ISM, referenced Revit models and a final file upgrade, FEG was able to deliver weekly updates to the owner and integrated design team with minimal human interaction. and deliver all other required files from there, Fitzpatrick said. AECOsim features FEG took full advantage of the new features in the thenrecent release of AECOsim, such as the ability to place user- For accurate modeling and scheduling, FEG created one and twosided parametric connection cells that included all of the plate and Tool in RAM led to direct material savings costs. Professional Development Advertising Section Bentley Systems, Incorporated PDH 3
BIM enhances structural analysis regardless of project size engineers to move beyond the typical beams and columns an engineer gets from analysis to include more meaningful detail in their models. PC Studio and the datagroup system were leveraged on the project to create several parametric cells for structural components in the project. The inclusion of analysis capability for the proprietary SidePlate connection in RAM Structural System allowed FEG to provide a $15,000 savings in direct material steel cost on the Rehabilitation Center project. Although the SidePlate connection was conceived for high-seismic applications, it has demonstrated savings in lower seismic regions as well not only in terms of direct material costs, but also in field inspection costs. Traditional seismic connections require continuous inspection of full penetration welds, whereas SidePlate connections are all fillet welds allowing for periodic inspection and less field testing. The inspection and testing cost was anticipated to save an additional $13,000. For accurate modeling and scheduling, FEG created oneand two-sided parametric connection cells that included all of the plate and weld components for the design. As the connection component was placed, the engineer received immediate visual feedback. If the parameters entered were correct, the cell would fit snugly around the column and beams for that condition. If column flanges extended beyond the side plates or the cover plates were not snug to the beam This workflow enabled FEG to share accurate data with the fabricator and provide a Revit deliverable. 4 PDH Professional Development Advertising Section Bentley Systems, Incorporated
flanges, the user could tell something was wrong with the parameters and take action to correct it right then rather than dealing with an RFI during construction. Column base plate parametric cells were created that included anchor bolts, nuts, washers, embedment depths and a non-plotting clearance lug at the bottom of the anchor bolt. If this (red) lug was visible from the underside of the foundations, we knew the footings were too shallow or the bolts too long for that condition and the anchor bolts would not have the proper concrete cover. Anchor bolt layouts could be visually compared against the column profile for clearances during placement. The base plates and anchor bolt layouts were included on the extracted foundation plan offering another opportunity for FEG to discover inconsistencies in its modeling. The engineering team created spread footing parametric cells to allow them to consistently model footing sizes, reinforcing quantities and elevations. It also ensured enforcement of FEG s corporate designs. Beam web openings, necessary for proper coordination and interference detection, were created and scheduled as well. Datagroup annotations were placed on our drawings for each of these parametric elements, closing the loop on accurate coordination between our model and plans and enforcing corporate standards for labeling each of the elements. The risk associated with transferring red marks the old way was eliminated and consistency between FEG s model and drawings was assured. By leveraging a VBA macro during placement of the annotations, FEG easily enforced corporate standards for the call-outs on the plan and ensured drawing consistency. AECOsim also gave the FEG team the ability to modify or rework exported datagroup information via macros in the schedule templates. FEG made extensive use of macros in all of their schedules to reformat or combine data when necessary and standardize the schedule layout. The engineer/user simply clicked a button on the exported data spreadsheet to run a macro, thereby eliminating poetic license to format the data as the user would like to see it and enforcing FEG s corporate standards. Running macros on all of the schedule data from the model also allowed FEG to screen for inconsistencies. For example, all the elements with Mark ID A1 could be verified to have the same values assigned to all the data parameters for that element. If a discrepancy was discovered, an error message would be displayed in the schedule to alert the user that something is FEG s schedules extremely simple and assured consistency between their model and construction schedules. The i-model plug-in for Revit allowed FEG to reference in the MEP model for internal coordination and run a cursory interference check on the structural model for clashes. Although the placement of the parametric cells in FEG s structural model was a bit more labor intensive than the engineer s traditional process, the benefit of accurate Spread footing parametric cells allowed the engineering team to consistently model footing sizes, reinforcing quantities and elevations. 2D plans were delivered as well, but had much less detail than the 3D parametric model. Professional Development Advertising Section Bentley Systems, Incorporated PDH 5
This fully detailed structural model of the Rehabilitation Center was passed on to the general contractor after design. scheduling and error checking, visual consistency, checking of FEG s design during element placement and controlled drawing annotation far exceeded the extra work and significantly reduced the risk of coordination errors on our drawings. By creating parametric content with PCStudio, we were able to provide an immediate visual confirmation of modeling accuracy during element placement, Fitzpatrick said. The user was able to see the new content in full context of the model and could tell if the assigned parameters fit the current condition. This visual confirmation provided the first level of conformance and error checking. This project demonstrates that mega projects by mega-sized firms are not the only ones using Bentley Building applications to solve unique challenges, work and thrive in a mixed BIM environment, gain sustainable drawing production efficiencies and deliver more consistent drawings using the powerful set of tools in AECOsim. The innovative Bentley products have allowed this small firm to surpass industry standards and set itself apart as a leader by developing an advanced solution to today s BIM workflow. Doug Fitzpatrick, P.E., LEED AP is the founder, president and practicing engineer of Fitzpatrick Engineering Group, a eight year old structural engineering firm specializing in commercial and healthcare building design. He has a total of 30 years of national and international structural engineering experience. His firm was an early adopter and is an advocate of BIM and has been actively using Bentley Structural/AECOsim for six years and Revit for three years to share model data with the design and construction teams. He actively provides lunch-n-learns to clients educating them on BIM from a structural perspective and has spoken at several industry conferences including NASCC and Bentley as well an SE University interoperability webinar. Jeff Yoders is technology editor and webcast coordinator at ZweigWhite. For five years, he covered IT, CAD, and building information modeling (BIM) as senior associate editor of Building Design + Construction. He s a chair at-large of the Associated General Contractors of America s BIM Forum and has won four American Society of Business Publications Editors awards. 6 PDH Professional Development Advertising Section Bentley Systems, Incorporated
BIM enhances structural analysis regardless of project size Go to http://continuingeducation.zweigwhite.com to take the following quiz online. Quiz answers will be graded automatically and, if you answer at least 80 percent of the questions correctly, you can immediately download a certificate of completion. 1. The owner on the Rehabilitation Center project required a Revit model and what other requirement of the project team? a) That they use AECOsim b) Design team, contractor and major sub-contractors all on board as a highly collaborative team from the first meeting c) That sub-contractors be involved in design d) All of the above 2. The combination of a Revit deliverable and sharing the engineer s model data with the fabricator presented a particular challenge for Fitzpatrick Engineering Group because: a) Getting information out the way everyone wanted it to be sent was challenging b) Detail for connections was all 2D on the project c) No weld information was included d) The model did not have the ability to handle enough detail 3. To share structural information in all of the necessary formats, FEG did what? a) Relied entirely on 2D documents Integrated Structural Modeler (ISM) d) None of the above. 4. In the beginning of the Rehabilitation Center project, in fall of 2011, FEG performed an internal study of the ability of AECOsim and Revit to share information with a steel fabricator via what file format? a) IFC b) CIS/2 file c) RVT d) DWG 5. How did FEG get beyond its program version interoperability snag? a) Resorted to 2D documents for some parts of the project b) Left some parts of the project undetailed c) Electronic transfers using the RAM->Revit and RAM->AECOsim link, ISM, referenced Revit models and a final file upgrade d) All of the above 6. User-defined content allowed FEG s engineers to: a) Get information out the way everyone wanted it to. b) To move beyond the typical beams and columns an engineer gets from analysis to include more meaningful detail in their models. c) Create several parametric cells for structural components in the project d) All of the above. 7. The inclusion of analysis capability for the proprietary SidePlate connection in RAM Structural System allowed FEG to provide: a) Detail connections to SidePlates that otherwise would not be done b) Make seismic calculations in the model c) A $15,000 savings in direct material steel cost d) No significant difference in design 8. For accurate modeling and scheduling, FEG created: a) Details of all connections b) One-and two-sided parametric connection cells c) Exact steel beam and post sizes d) None of the above 9. Anchor bolt layouts could be visually compared against a) The column profile for clearances during placement b) The Revit model c) The AECOsim model d) None of the above 10. The engineering team created spread footing parametric cells to allow them to consistently model: a) Column flanges b) SidePlates c) Beam connections d) Footing sizes, reinforcing quantities and elevations Professional Development Advertising Section Bentley Systems, Incorporated PDH 7