非阻塞性微颗粒阻尼柱阻尼特性的实验研究

Experimental investigation on damping characteristics of NOPD columns

针对三个非阻塞性微颗粒阻尼空心柱,分别采用铁粉、铅粉和砂粒作为填充颗粒,通过自由振动实验,研究颗粒填充率、质量比、空腔结构形式、颗粒材料类型等因素对构件阻尼特性的影响,探索构件的合理空腔结构形式。实验结果表明:颗粒填充率和质量比是柱阻尼的显著影响因素,设计颗粒阻尼柱时选取合适的质量比或填充率可以获得最大程度的阻尼增大效果。另外,多空腔结构形式、多空腔填充颗粒方案以及选用合理的颗粒材料类型均有助于柱阻尼的提高。不管采用金属颗粒还是非金属颗粒,颗粒质量比宜控制在0.3～0.5的范围。当颗粒用量不大时,选用铅粉、铁粉等金属颗粒比采用非金属颗粒能获得更大的结构阻尼。实验结果可为非阻塞性微颗粒阻尼柱的合理设计提供依据。

For three hollow columns with non-obstructive particle damping, the influences of factors such as particle filling ratio, mass ratio, cavity configuration and particle material type etc. on the damping characteristics of columns were investigated by means of free vibration experiments, using iron powders, lead powders and sand grains as filling particles respectively. The reasonable structural configuration of cavity was explored. Test results indicate that particle filling ratio and mass ratio are the principal influencing factors for the damping of columns and that the damping effect on columns may be achieved to maximal extent by rational choice of mass ratio or filling ratio in designing non-obstructive particle damping columns. In addition, the application of multicavity configuration and multicavity particle filling scheme, and the adoption of suitable material type of particles are beneficial to the damping enhancement on columns. No matter metal or nonmetal particles are adopted, the mass ratio should be controlled in the range of 0.3 to 0.5. If only small amount of particles is filled, higher structural damping can be acquired by using metal particles such as lead powders and iron powders than by using nonmetal particles. The experimental results may provide the basis for the rational design of non-obstructive particle damping columns.