基于跨点导纳法识别工程结构模态参数

提出了基于环境激励下，运用跨点导纳法识别大型工程结构模态参数的一种方法。叙述了跨点导纳法理论的基本定义和原理，跨点导纳法运用结构的输出自功率谱求出结构的主频率，运用结构的输出响应谱比值确定结构的振型，从而识别出环境激励下工程结构的模态参数。并结合传统模态试验原理，对一个平面薄板进行了两种对比试验，试验结果显示跨点导纳法识别结构的模态参数与传统的模态试验是一致的。分析表明跨点导纳法能够准确有效地辩识工程结构的模态参数。

To Identify Engineering Structures Modal Parameters Based on A Method of Cross-Point Admittance

A method of cross-point admittance based on ambient excitation to identify large engineering structures modal parameters was reported in this paper.The basic definitions and theories of cross-admittance were given,and according to cross-admittance theories engineering structures' dominating frequencies were educed and modals were reasoned out from output frequency response spectrum,so the engineering structures modal parameters were inferred.After check experiments on a thin plate were done based on theories of cross-admittance and traditional model experiment theory,the experiments' result showed that the identified modal parameters of the two methods were consistent.The analysis of this paper indicated modal parameters of engineering structures can be given exactly and validly with cross-point admittance theory.