Gengrui Wei

BS from Tongji University

MS from University of Illinois at Urbana-Champaign

Research Project: Computational Study of Tension Field Action in Metal Building Gable Frame Panel Zones

Gable metal frames are popular, cost-efficient structural systems for commercial and industrial buildings. The use of relatively thin web material typically leads to buckling of the panel zone in the beam-to-column connections when such frames are subjected to lateral loads. The panel zones may still be capable of developing post-buckling resistance by means of tension field action (TFA). Previous experimental research has shown that the exterior corner of a panel zone in gable frame knee joints may not be stiff enough to fully develop TFA. This study presents a theoretical model for TFA in knee joints based on plastic analysis, and an accompanying equation for predicting the post-buckling panel zone strength for positive bending (wherein the tension field is oriented from the interior to the exterior corners). To calibrate the proposed equation, a parametric analytical study was conducted using the finite element method. The study involved 98 prototype gable frame configurations and allowed the investigation of different design parameters on the TFA. The proposed equation was found to predict the panel zone shear strength for the prototype frames with an average error of 1% and an error standard deviation of 5%. Therefore, the equation can be used to calculate the post-buckling shear strength of panel zones for the range of design parameters considered in the parametric study.

Research Project: Steel Diaphragm Innovation Initiative (SDII)

The Steel Diaphragm Innovation Initiative (SDII) is a multi-year industry-academic partnership to advance the seismic performance of steel floor and roof diaphragms utilized in steel buildings through better understanding of diaphragm-structure interaction, new design approaches, and new three-dimensional modeling tools that provided enhanced capabilities to designers utilizing steel diaphragms in their building systems. SDII was created through collaboration between the American Iron and Steel Institute and the American Institute of Steel Construction with contributions from the Steel Deck Institute, the Metal Building Manufacturers Association, and the Steel Joist Institute in partnership with the Cold-Formed Steel Research Consortium; including, researchers from Virginia Tech, Johns Hopkins University, Northeastern University, and Walter P Moore. Detailed description and updates for this project can be found at http://steeli.org/.