Experimental And Theoretical Study Of D-Type Eccentrically Braced Steel Frames With Reinforced Connection Under Cyclic Loading

Structures located in seismic regions must be designed to resist considerable lateral inertial loads. A number of structural steel systems satisfy a part of these requirements. Ordinary steel moment-resisting frames (MRFs) are known to possess excellent energy dissipation, but they are relatively flexible and can become uneconomical if substantial lateral stiffness is required. Concentrically braced frames (CBFs) offer considerable strength and stiffness, but their energy dissipation and inelastic behavior can be poor because of the buckling of the brace. Eccentrically braced frames (EBFs) are a lateral load-resisting system for steel buildings that can be considered a hybrid between conventional moment-resisting frames and concentrically braced frames. EBFs are in effect an attempt to combine the individual advantages of MRFs and CBFs, while minimizing their respective disadvantages.In this dissertation the design and quasi-static experiment on a one-third-scale eccentrically braced model frames are described first. This is followed by a description of the inelastic behavior of EBFs modeling the experiment by means of the computer program ANSYS. The inelastic behavior of new D-type EBFs modeling by use of ANSYS is described next and compared with the former. The analysis indicated that a new beam-column connection could prevent active link from brittle fracture and move the link out of the column.Based on experimental study and theoretical analysis using the suggested design and construction methods can improve its seismic property. All these conclusions and suggestions will be useful for engineering and lay a foundation for further study.