Analysis and Design of Semi-Continuous Sway and Non-Sway Frames

Frames are traditionally designed as being perfectly pinned or perfectly rigid. These connections do not actually exist in real structures, with connection behaviour being between these extremes. Assuming that the connection is pinned leads to an overly conservative design as no moment transfer can occur at the connection, meaning bigger steel sections being used for the beams than are necessary.Site monitoring of the first building to make use of the semi-continuous design approach was conducted. The monitoring covered a primary and secondary beam during the construction and later loading of the structure. After the site monitoring the structure was modelled, using the ANSYS software package for finite element analysis. The results for this were compared to those from the site monitoring, and the results were found to be very close, so the model was used in further analyses.In the next set of analyses the connection stiffness and column base stiffnesses were changed, by making changes to the M-φ curve. It could then be seen how the joint stiffnesses affect the flexibility and strength of the frame. The model was then expanded to model multi-storey construction. Analysis techniques were used to show the trends that exist in the finite element results. These analyses were conducted on the results of frames with different section properties, different connection stiffnesses, and numbers of storeys.