Abstract:Structural dynamic characteristics are widely used in structural vibration control, structural reliability design and health monitoring, from which some basic concepts of dynamics need to be further discussed. An example of transverse vibration of a simply supported beam is used to analyze and calculate the response amplitude of a multi-degree-of-freedom system by modal displacement method and modal acceleration method, respectively. the relationship between structural displacement response and first-order natural frequency and the relationship between structural displacement mode contribution and modal strain energy are discussed. Based on the modal orthogonality, by analyzing the displacement response of the multi-degree-of-freedom vibration system, the necessary conditions of the system resonance are discussed, that is, while ensuring that the vibration frequency of the system (a certain natural frequency) is equal to the excitation frequency, the displacement response should also show the corresponding modal shape, and the pure modal resonance of the multi-degree-of-freedom system can be used to accurately identify the modal parameters of the structure.
张开银,孙齐,熊驷东,蒋紫玲. 结构动力学应用中若干基本概念的研究[J]. 振动与冲击, 2024, 43(4): 297-302.
ZHANG Kaiyin, SUN Qi, XIONG Sidong, JIANG Ziling. A study on some basic concepts in the application of structural dynamics. JOURNAL OF VIBRATION AND SHOCK, 2024, 43(4): 297-302.