Get our Standard and Special Profile Steel Joist & Deck Catalogs... FREE!
BIM steel joist design is now a reality
Our new building information modeling (BIM) steel joist design component contains joist configurations, specifications, material components, and design requirements that can be used from the planning room to the jobsite. The component is a Tekla software add-on. Additional components to come will support additional brands of 3-D design software.
The NMBS joist component will address three phases of digital steel joist project design. First is the “generic” joist object that can be used in the preliminary project stage. Second is the ability to use the generic joists information within the NMBS detailing-design process. Third is the final “as built” joist component that contains the actual joist configuration, end conditions and member sizes.
For more information about our new BIM joist design component and to be notified of its availability for free download, please click here.
Designing a more cost-effective gable joist
Recent construction of the South Carolina Governor's School for Science and Mathematics illustrates the range of cost accountability within steel joist design. In place of the conventional double-pitch gable design, in which triple pitch long-span joists are erected with a smaller gable joist set atop, New Millennium designed a three-piece Fink-Truss design, reducing cost at nearly every phase of design, delivery, assembly, and erection. Steel tonnage reduced by over 50% and resulted in 20% less manufacturing time, 67% less transportation costs with no wide-load requirements, reduced on-site storage space and a 66% reduction in erection labor and 60-ton crane costs.
The gable joists had an overall length of 92 feet and the profile had a center depth of nearly 16 feet. In lieu of a standard gable approach, the three-piece gable design met the architect’s esthetic requirements, while cutting erection labor and crane time by two-thirds.
For a full report on this project, see the “Manufacturer’s Turn” article in the July edition of Structural Engineering & Design magazine.
Three-piece Gable Joist
Standard Gable Joist
Collaborative vs. Conventional: In lieu of a standard gable approach, a three-piece gable design (top image) met the architect’s esthetic requirements, while cutting erection labor and crane time by two-thirds.
Increasing seat depth can cut project costs
An initial design calls for 16K3 joists for a 20ft span and with a 5ft top chord extension. The engineer has specified an R10 (SJI table) with a 2-1/2” deep seat. To meet the R10 criteria, the joist requires a larger top chord and bearing angle. A solution is to increase the seat depth to 5” and meet the R10 criteria using a standard top chord and bearing angle. This provides the required design strength and stiffness with less steel – a 40% material savings that translates into a range of cost reductions to the project by way of less manufacturing, transportation, on-site handling and storing, and reduced erection hours.
The new BIM steel joist design component enables earlier completion of the steel package design, while preventing a range of miscommunication costs.
New Millennium Building Systems is a wholly owned subsidiary of Steel Dynamics Inc.
