Investigating the Seismic Design Parameters of Divergent Dual-Braced Frame System
• Investigating the effect of the link beam length on the coefficients of seismic response modification of divergent dual braced structures
• Investigating the effect of height on the coefficients of seismic response of divergent dual-braced structures
• Estimation of seismic response modification coefficients using nonlinear static analysis.
• Representation of the relation to calculate the coefficient of behavior and deflection amplification factor in divergent dual braced frames
Introduction of Seismic Modification Response Coefficients
In the divergent braced frames, a portion of the beam between the braces and the column or between the two braces is called the link beam.
Eccentric Braced Frame (EBF)
In 1972, in Japan, Fujimoto and colleagues carried out research on these systems.
More general research on this system was conducted in the United States and in 1977 by Popov and his colleagues at the University of California, Berkeley.
In 1980, the first building was constructed using this system which was the 19-story building of the American Bank in California.
In the mid-1980s, during a laboratory research program at the University of California Berkeley, braced steel frame buildings were studied.
Results obtained from static nonlinear analysis
The position of the formation of bending plastic joints in the 5-story model with the link beam length of (e = L / 2)
Base shear-displacement chart of the roof for a 10-story model:
The type of yielding of the link beam (shear or flexure) is effective on the structure's period and by increasing the length of the link beam, the period of the structure increases. The proposed relationship is based on the height of the structure for the determination of the period of the steel structure with a divergent dual braced system by ASCE 7-10 regulation. Thus, in view of the results, it is recommended that the effect of the link beam length should be considered in determining the period of divergent dual braced structures. As the height increases, as well as with the increase in the length of the link beam, the ductility coefficient and the reduced coefficient of ductility decrease. The link beam length is a very important parameter in increasing the ductility of divergent dual braced structures. The deflection amplification factor decreases with increasing height as well as with the increase in the length of the link beam.
In general, taking into account a single behavior coefficient and a deflection amplification factor for all divergent dual braced frames are not appropriate in the regulations, and the effects of the length of the link beam and the height of the structure in providing the behavior factor and the deflection amplification factor must be interfered.
Objectives of the site in presenting this project
This project examines the “Seismic Design Parameters of Divergent Dual-Braced Frame System”.It could be helpful for university students, researchers and etc which can be utilized in scientific and industrial projects, and MSc and PhD theses.In some cases, university students require investigation and research for their MSc and PhD theses. Since the present project consists of a complete project and includes all university flowcharts, it could prove useful.