本文根据原型振动实测的位移记录,应用时间域识别法,求得了结构的前几阶模态的固有频率和阻尼比.本文还根据Ibrahim提出的模态置信因子的概念,定义了模态频率置信因子和阻尼比置信因子,从而能更准确地确定识别到的结构模态参数的可靠程度. In this paper, based on the measured displacement records of the prototype vibration, the natural frequency and damping ratio of the first several modes of the structure are obtained by using the time domain identification method. This paper also defines the modal frequency confidence according to the concept of modal confidence factor proposed by Ibrahim. Factor and damping ratio confidence factors can more accurately determine the reliability of the identified structural modal parameters.