基于大坝实测性态的数据特征，开展了大坝服役性态监测数据序列的频谱分析研究，并从系统辨识的角度，构建了大坝效应量与影响量的相干关系分析模型，以期从频域内揭示大坝实测性态的时程变化规律，并对其成因作出量化解析。结合工程实例，对比分析了大坝原型监测数据序列时域分析与频域分析成果，验证了文中所述方法的可行性和有效性。

This research was to reveal the variation regularity of observed dam behavior in the frequency domain, and to make quantitative analysis on the causes of variation. With a gravity dam as a case study, we analyzed the spectrum of monitoring data sequence of dam behavior in service, and established a model to analyze the coherence relation between effect quantity and influence quantity from the aspect of system identification. Through comparison between the results of time-domain analysis and frequency domain analysis of prototype monitoring data sequence, we confirmed the feasibility and validity of this approach.