运行过程中的水电站厂房支承结构动荷载的作用复杂，确定支承结构动力特性是水电站厂房动力分析中的重要问题，然而常规的试验手段对结构有较强的破坏作用或者因难度较大不易实现。利用李家峡双排机主厂房真机试验中的测试数据，基于动力学原理分析了停机过程中结构振动及荷载的变化的特点，提出了一种应用停机过程识别厂房支承结构动力特性的方法。在该方法中，将机组测试与结构测试成果相结合，并充分利用小波分析的优点，成功地克服了停机过程分析中荷载变化历程长，结构振动非平稳等不利因素。

During running process, the effect of dynamic loads is quite complex. So determining dynamic characteristics of supporting structure are of great importance when making hydro plant's dynamic analysis. However, conventional testing measures often cause intensive destruction or are too complicated to implement. In order to solving above problems，this paper，basing on principle of dynamics, applies the test data to analyze the structure vibration and variability of loads during machine halting process，and further puts forward a new method to identify dynamic characteristics of hydro plants supporting structure using machine halting process. The test data comes from prototype observation in Lijiaxia's power house structure of two-row placed units. The method, combining unit test and structure test result, and fully using advantage of wavelet analysis, successfully overcomes poor factor like long variation time of loads，vibration fluctuation，etc.,when analyzing halting problem.