Comprehensive Revision of Design Considerations for Column Base Connections in Steel Moment Frames

Comprehensive Revision of Design Considerations for Column Base Connections in Steel Moment Frames

Column base connections are arguably the most critical connections in Steel Moment Frames (SMFs), transferring forces from the entire structure into the foundation. The role of these connections is even more critical in the seismic response of SMFs because their strength, rotational stiffness and hysteretic characteristics interact with the frame, influencing force/moment distribution in the frame. This study will expand upon the available data on SMF column base connections and force transfer mechanisms including exposed with base plate and anchor rods, embedded and slab over-topped connections. The results will provide validated way to design and model these connections.

Specific objectives of the proposed research are:

To develop and disseminate fundamental understanding of the force transfer mechanisms of commonly used and previously untested embedded base connections (including those with an overtopping slab) under monotonic and cyclic loading.

To develop design methods/procedures and criteria for these connections that result in economical and reliable column base connections.

To develop and investigate repairable base connections, and their viability within seismically designed moment resisting frames.

To integrate connection response (developed in this and previous studies) with building response to develop strategies that fully leverage interactions between base and frame to obtain economical and safe designs.

To develop design aids, examples, software and other tools to facilitate the adoption of these new design insights and methods by the engineering practice.

To attain building code changes that adopt the products of this research in an effective and timely manner.

This study is follow-on to the previous study and findings reported in the Embedded Column Base Connections Subjected to Flexure and Axial Load: Tests and Strength Models (CPF Grant #03-11).