目前水工结构的动力破坏特性越来越受到关注，其中动力特性是其研究的一个重要方面。通过模型试验的方法研究重力坝模型动力特性的测试方法。重点研究了环境激励法测试结构动力特性的效果，并与传统测力法进行了比较。试验结果表明采用环境激励的方法，可只根据结构的振动响应数据，有效地测试结构的动力特性。并且在不同大小环境激励下结构的振型没有发生变化，频率与阻尼比变化很小。试验结果还表明通过环境激励法与通过传统激励法测试的振型、频率与阻尼比相差很小，可认为采用这两种方法测试的结构动力特性一致。同时还说明环境激励法可有效地测试有损伤结构的动力特性。试验结果为使用环境激励法测试实际在线重力坝结构的动力特性提供了依据。

Abstract: The damage behavior of hydraulic structure caused by dynamic load attracts more attention at present, and is affected deeply by dynamic properties of the structure. In this work, the testing method of dynamic property of a gravity dam is studied by model test. The ambient vibration testing method was studied mainly and compared with traditional testing method. The experimental results show that ambient vibration testing method can measure the structural dynamic property effectively by structural dynamic response. The mode shape, frequency and damping ratio of model structure is affected lightly by magnitude of ambient excitation. The testing results of dynamic property of model structure are coincident by ambient vibration testing method and traditional testing method. The experimental results also show that ambient vibration testing method can detect the dynamic property of structural damage effectively. The experimental results verify further its effective to structural dynamic property of in suit detection based on ambient vibration.