A composite joist (CJ-Series) is a steel joist designed for shear connection to the overlying concrete slab using field applied shear studs, such that when the decking is filled with concrete, the shear studs become embedded in the hardened concrete and a unified load bearing system is created that deflects as a single unit. Advantages can include a stronger, stiffer, lighter and less cost steel structure compared to other structural steel frame approaches. These advantages need to be evaluated based on offsetting costs for field installation of the shear studs. The specifying engineer may also consider composite decking. For more information, see the SJI CJ-Series catalog.
- Reductions in steel material and related costs
- Open web joists allow routing of MEP for lower floor-to-floor height
- Wider spaced and fewer columns for more open bays
- Stiffer floors for reduced live load deflections and reduced vibration
- Shortened construction timeline