The characterization of the dynamic behavior of an arch dam, and its evolution throughout the structure's lifetime, provides important data for the safety control process. Forced vibration tests remain a reliable technique for this purpose. The Baixo Sabor dam is a 123 m high arch dam recently built in Portugal. Forced vibration tests were performed before and after the reservoir filling. Two techniques for forced vibration test are compared, discrete frequency scanning, the standard methodology, and continuous frequency scanning (sine sweep), a new proposed methodology, which allowed faster results without loss of precision. For the interpretation of test results two numerical models of the dam‐reservoir‐foundation system were built, and calibrated with the experimental data. A good match of numerical and experimental results was obtained for the six lowest frequencies and corresponding mode shapes.

中文翻译：

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通过强制振动试验和数值模型表征混凝土拱坝的动力特性

拱坝动态特性的表征及其在结构寿命中的演变，为安全控制过程提供了重要数据。为此，强制振动测试仍然是可靠的技术。Baixo Sabor大坝是最近在葡萄牙建造的123 m高拱坝。在储层填充之前和之后进行强制振动测试。比较了两种用于强制振动测试的技术：离散频率扫描（标准方法）和连续频率扫描（正弦扫描），这是一种新提出的方法，可以更快地获得结果而不会损失精度。为了解释测试结果，建立了大坝-水库-基础系统的两个数值模型，并用实验数据进行了校准。