This article by Dylan Richard, PE, and Stephen Blumenbaum, PE, originally appeared in the December 2022 issue of Structure Magazine.
Overview
As part of an ongoing campus improvement program, the University of Florida and the University of Florida Police Department in Gainesville, Florida, recently commissioned their new Public Safety Building (PSB) located in the heart of the campus. The 50,792-square-foot three-story PSB consists of concrete tilt-up wall panels for the exterior and is supported by structural steel on the interior. The entire scope of the project also included a 6,931-square-foot renovation of the adjacent existing Centrex Building, which houses the University’s Emergency Management staff and emergency operations dispatch center.
The University of Florida contracted with Ajax Building Co. to provide pre-construction and construction services for the project, which consolidated five previous police department locations across campus under one roof. Ajax partnered with Walter P Moore, the engineer of record, on the PSB project to provide expedited bid documents and an advanced bill of materials for concrete and structural steel, as well as submittal and shop drawings for the subcontractors. This reformatted delivery process created schedule savings and improved coordination between trades.
According to BNG Construction, the concrete contractor, and Trinity Fabricators, the steel contractor, the shop drawings were ready soon after the contract was awarded—similar to a design-build job. Because Bluebeam Studio was also used on the PSB project, any updates to the drawings were registered in real-time. The upfront costs on the PSB project were offset by competitive concrete and steel bids because the subcontractors were not required to include the in-house engineering costs. Ultimately, the savings were part of the final guaranteed maximum price and resulted in savings that were passed back to the university.
LOD400 BIM Model
Walter P Moore designed each stage of the PSB’s construction documents using Autodesk’s Revit Building Information Modeling (BIM) software and Bluebeam Studio for architectural, structural, and MEP drawings. A Level of Development 400 (LOD400) BIM model was used for fabrication and assembly where the model element is graphically represented within the model as a specific system, object, or assembly in terms of size, shape, location, quantity, and orientation with detailing, fabrication, assembly, and installation information.
A coordinated effort with key building team members resulted in developing a BIM execution plan. This plan was implemented during the PSB project’s design, pre-construction, and construction phases.
A detailed analysis of the concrete and structural steel com-ponents was performed regarding the project’s timeframe during pre-construction and construction. The comparative analysis was performed so Ajax could determine if there would be value to the project utilizing Walter P Moore’s reformatted delivery process. This analysis was essentially Ajax’s go/no-go evaluation. It compared the actual timeframe that Walter P Moore released deliverables before construction—including bid documents, preliminary reports, advance bill of materials, LOD400 model, and shop drawings—to what would have been the standard process of having subcontractors perform this work after a guaranteed maximum price was agreed upon with the university.
The actual timeline for the PSB project—which again benefited from this reformatted delivery process—revealed significant time savings compared to a typical project timeline. In the PSB timeline, the rebar was released for fabrication on June 7, 2021, and delivered to the site three weeks later. If a post-guaranteed maximum price timeline had been used, the rebar would not have arrived onsite until August 9, 2021—a six-week improvement in rebar delivery. The structural steel comparison shows steel ready for delivery on July 9, 2021. In comparison, the post-guaranteed maximum price option was September 6, 2021 – an eight-week difference in expedited delivery. As a result, after considering other critical path items unrelated to structural scope, the PSB project shaved approximately one month off of construction, which was eventually carried through to the completion of the project. The significance was that the structure was completed a month sooner than it would have been had Walter P Moore’s reformatted delivery process not been used, allowing follow-up trades to begin their work sooner than originally scheduled. This month time savings also carried directly through to the completion of the project.
In addition to the PSB project, part of Walter P Moore’s overall scope of work included the renovation of the Centrex Building, which was initially constructed in 1967, expanded in 1973, and renovated in 1985. A BIM model was also developed for the existing building based on construction documents from its various phases and site visits. For this project, the interior of the building was gutted and reconstructed. Additionally, two cast-in-place concrete columns were removed and replaced with new steel transfer beams supported by widened and strengthened cast-in-place concrete columns and foundations. Walter P Moore also detailed the new steel and cast-in-place concrete reinforcement for the Centrex Building.