泡沫铝/聚氨酯复合材料摩擦阻尼器性能试验研究

基于泡沫铝/聚氨酯复合材料（aluminum foam/polyurethane，简称AF/PU）是一种同时具有铝材料的摩擦性能和聚氨酯的黏弹性的复合材料，由此研制出一种能够发挥黏弹性阻尼器和摩擦阻尼器各自耗能特点的泡沫铝/聚氨酯复合材料摩擦阻尼器（AF/PU摩擦阻尼器），并对该阻尼器进行位移幅值、频率等相关性的性能试验和疲劳性能试验。以最大输出力、刚度和阻尼比为指标，研究该阻尼器的性能规律，采用修正的Bouc-Wen计算模型模拟其滞回曲线，并对比模拟结果和试验结果。研究结果表明：AF/PU摩擦阻尼器的滞回曲线饱满，具有较高且稳定的阻尼比。该阻尼器的力学性能随位移幅值和循环次数的增加而呈现分阶段性，但是加载频率的影响却较小，该阻尼器是一种典型位移幅值相关的变刚度摩擦阻尼器。修正的Bouc-Wen模型的模拟结果与试验结果二者吻合良好。

Experimental study on a friction damper of aluminum foam/polyurethane interpenetrating phase composites

As the aluminum foam/polyurethane composite (AF/PU) is a kind of composite which combines the viscoelastic behavior of polyurethane with the friction behavior of aluminum, an innovative friction damper (i.e. AF/PU friction damper) was developed by using AF/PU. In order to verify the advantages of the AF/PU friction damper which can possess viscoelastic damper and friction damper in energy dissipation, the AF/PU friction damper was examined based on a serial of tests with different loading frequency, displacement amplitude and loading cycles. Based on the performance indices such as the maximum force, stiffness and damping ratio, the mechanical properties of AF/PU friction damper were studied. The modified Bouc-Wen model was proposed to simulate the hysteretic curves of AF/PU friction damper, and then the simulated results were compared to the experimental results. The results show that the AF/PU friction dampers exhibit the full hysteresis loops and possess high and stable energy dissipation capacity. The AF/PU friction damper is a typical displacement amplitude-correlated and variable stiffness damper, and its mechanical properties are not sensitive to the loading frequency, but appear to be multi-phased with the increase of displacement amplitude and cycles. It is also found that the simulated results from the modified Bouc-Wen model agree well with the experimental results.