Abstract：The friction pendulum system (FPS) has good isolation and self-centering performance and is widely used in engineering practice. The friction material of the sliding pair is critical for the seismic performance of the isolator. The dynamic friction behaviors of polytetrafluoroethylene (PTFE), ultra-high molecular polyethylene (UMHWPE), polyoxymethylene (POM), high-density polyethylene (HDPE), and polyethylene terephthalate (PET) at different compressive load and sliding rates were studied experimentally. The variation rules of cyclic degradation and viscous-slip phenomena under different peak sliding rates and different pressures were illustrated. The effects of instantaneous sliding rate (ISR) and vertical pressure on the dynamic friction coefficient (DFC) are studied. Furthermore, the wear resistance of materials is presented. The results show that the cyclic degradation of POM is obvious, the viscous slip of HDPE is obvious, and the wear resistance of PTFE and HDPE is the worst. The DFC increases with the increase of ISR and decreases with the increase of pressure. The exponential model presents better than the logarithmic function model in fitting the relation between DFC and ISR. For the high ISR case, the DFC was verified by establishing the molecular dynamics (MD) model, and the error of MD for low ISR was 12.3%-14.2%. The MD was used to simulate high ISR, and the exponential model was used to fit the experimental and simulated data of FSP. With good fitness, the model could be used to estimate the DFC for high-speed sliding.
李宁1,2,3，王徐1，李忠献1,2,3. 考虑压强、速率影响的FPS材料动摩擦试验与模拟研究[J]. 振动与冲击, 2023, 42(22): 155-162.
LI Ning1,2,3，WANG Xu1，LI Zhongxian1,2,3. Experimental and simulation study on the dynamic friction of FPS materials considering the effects of different compressve loading and sliding rate. JOURNAL OF VIBRATION AND SHOCK, 2023, 42(22): 155-162.
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