Modern Steel Construction March 2012 : Page 33Partial view of the steel structure. Steel frame using SidePlate connections. ➤ have significantly escalated building costs when compared with the versatility of steel. The second was time. Selecting a steel frame ensured the structure could be enclosed before winter, allowing interior work, such as drywall, HVAC ducting, plumbing and elec-trical, to continue even when the weather didn’t cooperate. The original architectural plans for the spine building and three separate units called for moment-resisting conventional steel frames, but required a staggering 359 beam-to-column moment connections. To stay within the project budget, the structural engi-neer investigated several ways to limit the extent of field welding required and thus reduce the costs associated with having so many moment connections. Bracing systems were considered, but quickly eliminated because they would interfere with the operational and functional require-ments. Then the team turned to the SidePlate FRAME system, which was a more economical option because of its strength and simplicity. Best of all, because of its stiffer moment connections coupled with improvements in the overall lateral frame layout of the building, SidePlate required only 199 moment connections, which translated into a 45% reduction when compared with conventional steel frames. This ensured fewer erection hours, field welding and field labor—all of which translated into an estimated savings of approximately $300,000 when compared to the original design. While initially viewed as a steel frame system created only for earthquake, bomb blast and progressive collapse design applications, SidePlate FRAME is rapidly becoming recognized by engineers, steel fabricators and general contractors in lower seismic zones as a cost-saver in wind-controlled regions as well. Today it is the only steel moment frame system that uses all fillet-welded construction, with all welds deposited in the horizontal welding position 2F, in lieu of complete joint penetration (CJP) groove welds, which can be costly and require ultrasonic (UT) inspection. The decision to use SidePlate on the project was unanimous, but there was one more hurdle. Because Eastern State Hospital is a state-owned building, open bidding is a requirement. Fortunately, SidePlate is a proven technology design—not a sole-sourced manu-factured item. That means it can be competitively bid by any and all steel fabricators, just like any other steel component in a project’s design documents. For the new Eastern State Hospital project, the SidePlate FRAME system offered several significant benefits, including: Sam rangaswamy, S.E., P.E., Ph.D., is principal-in-charge of rangaswamy & associates, Inc., a planning, engineering and management consultancy service based in louisville, Ky., which also maintains an office in India. he has more than 40 years of structural engineering experience in design, surveying and analysis in the public and private sectors. anthony Ehlers, Jr., has been a project manager and structural engineer for rangaswamy & associates since 2003. ➤ photos by rangaswamy & associates, Inc. Beam end of the connection. ➤ march 2012 MODERN STEEL CONSTRUCTION 33 Publication List Using a screen reader? Click Here |
