Theoretical And Experimental Research On New Type Variable Friction Damper

The friction damper is a shock absorption and energy dissipation device that relies on the friction between the contact surfaces to consume seismic energy and reduce the seismic response of the structure.However,the structural form and friction force of the traditional friction damper always remain unchanged,resulting in a constant damping force.For this reason,based on previous studies,this paper has developed a new type of variable friction damper that can produce continuously variable damping force,has strong adaptability and high energy consumption.The main research contents and results of this paper are as follows:1.On the basis of previous research,developed a new type of variable friction damper with variable damping force and stronger energy dissipation capacity,introduced its structural characteristics and working principle,and deduced the new type of variable friction damper restoring force analytical formula.Draw the hysteresis curve of the damper under specific parameters,and it can be seen that the hysteresis curve has displacement-dependent degeneration and its shape is similar to that of a saddle.2.Using ABAQUS finite element analysis software,the new variable friction damper solid model was simulated numerically to verify that it can play a stable role in the structure.Produce and carry out the mechanical performance test of a new type of variable friction damper,obtain a stable pommel-shaped hysteresis curve through the test,and calculate the equivalent stiffness,damping ratio and energy dissipation capacity and other mechanical performance indicators based on the test data.The test results are compared with the numerical simulation results,and then the correctness of the theoretical model is verified.3.The SAP2000 software was used to analyze the seismic response of the four-story frame structure with the new variable friction damper.Based on the mechanical performance test results of the new variable friction damper,a simplified trilinear model was proposed to simulate the mechanics of the damper.performance.Comparing the damping effect of the diagonal brace structure and the structure equipped with dampers,it is found that the structure with the new variable friction damper has a more obvious damping effect than the diagonal brace structure under the action of earthquake,and its damping rate can reach 63%.