Design And Numerical Analysis Of A Variable Friction Self-resetting Damper

The friction damper has the advantages of convenient materials,low cost,simple structure,easy installation and high energy dissipation capacity.However,the frictional dampers which are widely used in practical engineering can only provide a single and determined damping force,which leads to the fact that the frictional dampers cannot provide proper and variable damping force to dissipate energy under the action of different earthquake sizes.Furthermore,the general friction damper after the earthquake produced a large deformation can not continue to use,repair or replace the damaged damper will also increase the cost.So the paper is based on the basic principles of type friction damper,this paper proposes a variable friction since the reset damper,the damper type friction damper has been solved by the variable friction effect damping force of a single defect,join the shape memory alloy material damping apparatus for certain ability to the reset,the variable friction since the reset damper structure is simple,make convenient,can effectively control the structure response to the earthquake.The main research work of this paper is as follows:(1)The structural design of the variable friction self-resetting damper is put forward,the working principle of the damper is introduced,and the analytical formula of the mechanical calculation model is derived.(2)The variable friction self-resetting damper was simulated and analyzed by ANSYS Workbench finite element software.The simulation results show that the obtained force-displacement curve is consistent with the theoretical analysis of the force-displacement curve.By comparing the energy dissipation per unit cycle,secant stiffness and equivalent damping ratio under different preload conditions,it is concluded that the energy dissipation capacity of the damper is stronger with the increase of preload.The stress analysis of the damper in the whole travel range shows that the damper will not be damaged due to its strength.(3)Variable friction self-resetting damper is applied to structural vibration control.Through analysis and comparison under small and strong earthquakes is no control structure and control structure of different vibration response parameters of damping ratio,it is concluded that displacement between the floor absolute displacement of shock absorption rate over 40%,floor shear and residual deformation of the damping rate were all higher than 37%,explain the design of variable friction since the reset control of structure has good vibration damper,and can play the reset function.