| A shortcoming of current seismic design provisions for special concentrically braced frames (SCBF) is the gusset plate connection design. Current seismic design provisions require that the strength of connection exceeds the strength of the brace. These design provisions can result in large and uneconomical connections. Improved connection designs are needed to improve structural performance. These improved design methods are based on balancing the yield mechanisms and the failure modes of the critical structural elements. The proposed design procedures will be verified using finite element (FE) models. The ultimate goal of this research was to develop accurate and reliable FE models for predicting braced frame gusset plate connection behaviors. To achieve this goal, validated FE models were developed to predict the behavior of brace frames, to evaluate the influence of connection performance on the system response, and to provide appropriate design guidelines for gusset plate connections. A parametric study was conducted to extend the experimental research study. In addition, yield mechanisms and failure modes were investigated in this analytical study. The balanced conditions were also developed for the SCBF system. Finally, practical component models were developed and validated for seismic engineering of braced frame systems to assure good seismic performance at multiple performance levels. |
