Introduction to the hybrid steel frame with wood floor system

Abstract

The American Institute of Steel Construction (AISC) recently published a new design guide, Design Guide 37: Hybrid Steel Frames with Wood Floors. This new design guide intends to shed light onto a new form of construction not previously used in building construction. The new system is made up of a steel frame with wood floors rather than the traditional concrete-on-composite deck floors in steel construction that is popular today. The design methodology for this new system is not new. The steel frame design is completed in accordance with the AISC 360 Specification for Structural Steel Buildings, and the wood floor system is designed in accordance with the National Design Specification (NDS) for Wood Construction. Although design methods are not new, this new form of construction may lead to new considerations or nuances within the design that will need to be addressed. Considerations on fire protection, vibration, and potential composite action between the wood and steel are introduced and discussed in this report. A key design aspect that is changed is that the CLT slab acts as a continuous lateral brace to the top flange of the secondary beams, eliminating lateral torsional buckling. To show this new form of construction’s capabilities, a design example is completed and compared to that of a standard steel framed building. The comparison intends to illustrate this new system and the benefits that can be achieved by utilizing it in building construction.