Research On Energy Dissipation Shock Absorber With Displacement Amplification Functin And Shock Absorption Performance

In recent years,the technology of friction energy dissipation has been developed rapidly because of its excellent damping effect,and it has been widely used in practical engineering.The seismic input energy is consumed by friction energy dissipation devices to reduce the seismic response of the structure.However,there are some disadvantages for the existing frictional energy dissipation shock absorber such as the constant damping force in the fixed pre-tightening force,low energy consumption working in small displacement and bigger frictional damping force in bigger pre-tightening force.To overcome these deficiencies,a new type of energy dissipation shock absorber,which has function of amplifying displacement,was put forward in my study.By means of theoretical analysis and simulation,the scheme design,structure design,mechanical performance,damping performance and dynamic optimization design of the new friction energy dissipation damper are studied in detail.The specific research work and achievements are as follows:(1)This thesis states the principle of amplifying displacement and structural design scheme of this new type of shock absorber.After analyzing and calculating the mechanical properties,the nonlinear hysteretic characteristic curve of this new type of shock absorber is obtained,and it is compared with the existing friction type energy dissipation shock absorber.There are three characteristics for this new type of shock absorber such as magnifying displacement by more than six times,bigger frictional damping force in smaller pre-tightening force and saddle hysteretic characteristic curve,and the energy dissipation capacity of the new shock absorber is stronger than the existing shock absorbers.(2)The reinforcement effect of a new type of friction energy dissipation damper on plane steel frame structure was studied.The soil-structure interaction is considered when the damping structure is built,and the spring stiffness and damping coefficient of foundation soil were determined by time domain substructure method.flexible frame structure and the mechanical model of shock absorber are established by using ADAMS software.After static analysis of the new friction energy dissipation damping system,the relative displacement between the layers,the absolute layer displacement and stress distribution of the structure are investigated.The simulation results show that the new type of friction energy dissipation damper has a good reinforcing effect on the plane steel frame structure.(3)The damping performance of a new type of frictional energy absorber on plane steel frame was studied.Firstly,the dynamic simulation analysis of the new friction energy dissipation damping system is carried out,and then the amplitude-frequency characteristics of the structure system are studied.The simulation results show that the control of the relative displacement between the layers and the absolute layer displacement amplitude of the frame structure is better than that of the existing damper,and the absolute displacement amplitude of the top layer was reduced by 48%.Secondly,the time history analysis of the new friction energy dissipation system under the action of seismic load is carried out.The new type of shock absorber has obvious control effect on relative displacement between the layers,the absolute layer displacement,layer absolute acceleration and bottom shear force,and the control effect of these indexes is better than the existing shock absorber.The largest value of the decline rate is 34.71%,34.59%,34.79%,35.10%.(4)The dynamic optimization design of the new friction energy dissipation damping system is studied.The dynamic analysis of the damping structure system is carried out by drawing up feasible different shock absorber arrangement schemes.Taking the relative displacement between the layers and absolute layer displacement of the damping structure as the objective function,the optimal shock absorber arrangement scheme is obtained through the objective function.The calculation results show that the layout scheme of diagonal double-diagonal brace is better than that of herringbone double-diagonal brace,and its shock absorption rate is 33.83%.The layout scheme of triangular monoclinal brace is better than that of parallel monoclinal brace,and its shock absorption rate is 11%.