新型装配式竖向电涡流TMD试验研究

Tests for a prefabricated vertical TMD with eddy-current damping

针对城市大跨度钢结构人行天桥的减振需求,研制了一种结构紧凑、装配简单的新型装配式竖向永磁式电涡流TMD样机,综合TMD样机阻尼参数测试与电涡流阻尼磁场有限元分析结果提出了电涡流阻尼的初步设计方法与磁路优化布置。结果表明:新型TMD具有优良的阻尼特性、耐久性,且易于装配,工程应用可行性强。研究得到了用于竖向TMD的电涡流阻尼磁路优选构造:导体铜板两侧的矩形永磁铁宜采用同侧极性相同、不同侧极性相反的布置方式;永磁铁宜以水平单排布置为主,间距控制在永磁铁边长的一半以内;永磁铁必须安装2排或多排时,上下2排间距不宜小于永磁铁边长。

To meet vibration mitigation requirements of long-span urban steel footbridges,a novel vertical eddycurrent tuned mass damper（ TMD） was developed,it was compact and easy to assemble on site. On the basis of damping parameters test results of the TMD and magnetic field distribution of the eddy-current damping using the finite element analysis,the preliminary design method and the optimal magnetic circuit of eddy-current damping in a vertical TMD were put forward. The results showed that the developed TMD has excellent damping performances and high durability,it is easy to assemble,it is quite feasible for practical application. Moreover,the optimal magnetic circuit configuration for eddy-current damping in a vertical TMD was obtained. It was shown that rectangular permanent magnets on the same side of a copper plate should be the same polarity,while permanent magnets on the different sides should be the opposite polarity; permanent magnets are set in only one row,the horizontal distance between permanent magnets should be less than half of the length of permanent magnets; if permanent magnets must be arranged in two or more rows,the vertical distance between permanent magnets should be more than the length of permanent magnets.