| Nowdays,energy dissipation technology has been widely developed in structural applications,has become an effective measure to resist earthquakes and strong winds The low-yield-point steel shear damper has the characteristics of easy yield,relatively small size,strong energy dissipation capability,and low cost,so it has been widely used in engineering.In this paper,a four-piece shear damper was designed and manufactured using low yield point steel BLY160,and the hysteretic energy dissipation of the low yield point steel shear damper under cyclic reciprocating load was used by combining experimental research and finite element simulation Capability and low-cycle fatigue performance have been studied.The specific research contents are as follows:(1)The energy dissipation mechanism of shear-type dampers is analyzed,and four mechanical models suitable for low-yield-point steel shear-type dampers are introduced.(2)A quasi-static monotonic tensile test was performed on the low-yield-point steel BLY160 to obtain the basic material performance parameters such as the stress-strain relationship curve,Young’s modulus,and yield strength of the steel used in the test.Three types of shear dampers with different sizes were designed and tested for low-cycle reciprocating cyclic loading.The width-to-thickness ratio of the energy dissipation plate of the shear damper and the angular opening of the energy dissipation plate were investigated.The impact of low cycle fatigue performance,and analysis and summary of the hysteresis curve,skeleton curve,super strength coefficient,equivalent viscous damper coefficient,average energy dissipation index,etc.The results show that:low yield point steel shear type The hysteresis curve of the damper is very full,and it has excellent energy consumption performance without pinch.During the entire cyclic loading process,the strengthening phenomenon is very obvious,and there is no sudden change in strength and rigidity before the failure;the opening of the corner of the damper plate will improve the ultimate bearing capacity of the damper to a certain extent,but it will reduce its ductility,and Cause its energy consumption to be unstable.The higher the width-to-thickness ratio of the damper energy dissipation plate,the better its energy dissipation performance(3)Using the finite element analysis software Abaqus,the shearing damper of the test was selected for multi-linear strengthening and combined strengthening.The finite element simulation analysis was carried out,and the simulated hysteresis curve,skeleton curve and equivalent The viscous damping coefficient curve is compared with the test results.The results show that the results simulated by the two strengthening models can be very close to the test,but the curves simulated by the combined strengthening model are smoother and closer to the test curve,but more linear The enhanced model is more square.The reasons for the thin film effect of the damper in practical application are analyzed.The load capacity and energy dissipation performance of the ideal test state and the engineering conditions are simulated by changing the constraint conditions.The results show that:the energy dissipation plate will be produced in the actual project.The vertical film pulling force makes the hysteresis curve of the damper produce a certain impact on the energy consumption of the damper(4)The theory of low-cycle fatigue analysis is introduced,and several low-cycle fatigue life analysis models suitable for dampers are introduced.In order to reasonably estimate the low-cycle fatigue life of the steel plate energy dissipator,reduce the number of tests,and reduce the cost of the test,the fatigue analysis software Fe-safe conducted a finite element simulation of the stress field and fatigue life of the low-yield point steel damper.The results show that the damping The low-cycle fatigue life of the damper is greater than 30 turns to meet the requirements of the specification for the fatigue performance of this type of damper. |
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