Analysis On Hysteretic Behavior Of An Self-centering Eccentrically Braced Steel Frame Based On Shape Memory Alloy

Eccentrically braced steel frames are commonly used in engineering.They are widely used in domestic and foreign structures due to their good energy dissipation capacity,deformability and greater lateral stiffness.Eccentrically braced steel frame structure has its own unique component,which is called "energy dissipation beam section".Energy dissipation beam section is similar to "fuse" in physics,which can protect the structure to some extent.The energy dissipation beam plays a role in dissipating the seismic energy during an earthquake,but under the influence of a large earthquake,the residual displacement between layers of the structure after the earthquake will increase significantly,making it difficult to repair after the earthquake.In this paper,the shape memory alloy material is used to replace the steel of "energy dissipated beam section" in eccentrically braced steel frame structure.The self-reset eccentrically braced steel frame structure is formed by using the self-reset characteristic of shape memory alloy.Main research contents include:(1)Summarizes the reset function of the characteristics of shape memory alloy materials and the constitutive relation,the establishment of a steel frame structure finite element model,the energy dissipation beam section in the steel frame structure with shape memory alloy,and the use of ANSYS finite element software established fine since the restoration of eccentrically braced steel frame structure finite element model,through the numerical analysis,show that the shape memory alloy material of the energy dissipation beam section can minimize the residual deformation structure after the earthquake,since the restoration of steel frame structure present a good reduction effect.(2)In the reset eccentrically braced steel frame structure,by selecting different lengths of the energy dissipation beam section,different length of shape memory alloy is studied in the energy dissipation beam section,the hysteretic performance since the reset eccentrically braced steel frame structure,the influence of the different length of energy dissipation of the reset eccentrically braced steel frame beams,the strength,stiffness,since the ability to reset,and the effect of energy dissipation capacity.It is also shown that theshear yield energy dissipation beam section is superior to the bending yield energy dissipation beam section.(3)Selecting three different length the energy dissipation beam section,establish of eccentrically braced steel frame structure and the reduction of eccentrically braced steel frame structure finite element model,through the displacement loading analysis of the performance of the two structures,through the comparison of eccentrically braced steel frame with the reset eccentrically braced steel frame of the hysteresis curve,skeleton curve and stiffness degradation curve,the equivalent viscous damping ratio and residual displacement Angle,shows that since the reset eccentrically braced steel frame has a better energy dissipation performance,less residual deformation and better ability of the reset.