Damping Identification for the Stiffness Nonlinear Structure
Li Hui1, Sun Wei1, Liu Ying1, Han Qing-kai2
1.School of Mechanical Engineering & Automation, Northeastern University, Shenyang 110819, China;
2. School of Mechanical and Engineering, Dalian University of Technology, Dalian 116024, China
Abstract：There are a large number of structures, their natural frequencies will vary with the exciting levels and can be named as the stiffness nonlinear structures, such as the bolted joint structure, composite laminated plate structure, etc. Due to the effect of stiffness-nonlinear, the classical time domain and frequency domain methods of damping test will not be suitable to these structures. Therefore, on the basis of modified the classical half-power bandwidth method, this paper presented a method used to identify damping of the weak and strong stiffness-nonlinear structure systems. Based on the movement equation of the stiffness-nonlinear system, damping identifying formulas were derived respectively for the weak and strong stiffness-nonlinear structure systems. Then, damping test procedure was proposed for the above mentioned nonlinear structure systems. At last, a test case has demonstrated the practicability and effectiveness of this method, which was applied on damping test of a hard-coating cantilever thin plate with soft nonlinear characteristic and damping parameters were obtained under different exciting levels by sweep test.
李 晖1，孙 伟1，刘 营1，韩清凯2. 具有刚度非线性的结构系统阻尼参数测试[J]. 振动与冲击, 2015, 34(9): 131-135.
Li Hui1, Sun Wei1, Liu Ying1, Han Qing-kai2. Damping Identification for the Stiffness Nonlinear Structure. JOURNAL OF VIBRATION AND SHOCK, 2015, 34(9): 131-135.
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