US - Japan Composite and Hybrid Systems Research Program

Title of Project Moment Connections between Steel Beams and Concrete-Filled Tubular Columns
Principle Investigator Joseph A. Yura and James O. Jirsa
Title Professor, Professor
Institution The University of Texas at Austin
Mailing Address Ferguson Structural Engineering Laboratory, The University of Texas at Austin, 10100 Burnet Road, PRC Building 177, Austin, TX 78758-4497
Email yura@mail.utexas.edu OR jirsa@uts.cc.utexas.edu
Research Associates Bradley D. Koester, Ph.D. candidate, and Michelle A. Parsley, M.S. candidate
Research Sponsor National Science Foundation

Objectives

To develop design strength recommendations for the joint region of a steel beam to concrete-filled tube moment connection which employs the use of the split-tee through-bolt connection.

Technical Approach

In order to understand the behavior of the panel zone within the connection region, the project first looks at the failure mechanisms and characteristics of the panel zone when subjected to high shear through a stiff reaction frame (to simulate high shear due to reverse beam moments acting on the joint). The next phase of the project includes the design and testing of full or near full-scale moment connections that utilize the split-tee through-bolt connection.

Summary of Research Results to Date

Fifteen panel zone shear specimens have been produced. Varying the footprint of the contact area in which the shear was applied to the specimens had negligible effect on the strength of the panel zone in shear. Permanent panel-zone deformation was achieved through use of the stiff frame. Preliminary results indicate that the concrete compression strut achieved through the joint provided an ultimate shear strength of the panel zone that was 80 percent higher than the plastic shear capacity of the steel alone.

Keywords

concrete filled tubes, moment connections, panel zone, joints, shear, reinforced concrete/steel systems, connections, subassemblages; experimental investigation; analytical investigation
Back US - Japan Composite and Hybrid Systems Research Program