This study analyses the results from basin tests with a vertically sided cylindrical pile loaded by ice failing in crushing. Tests were performed with a ‘rigid’ structure and with structural models representing a series of single-degree-of-freedom (SDOF) oscillators covering a wide range of mass, frequency, and damping values. The structural models were represented by a real-time hybrid test setup, which combined physical and numerical components to measure real ice forces, apply the forces to a numerical structural model, and simulate the dynamics of the tested structural models in real-time. The test results are analysed and simple numerical simulations are performed to assess the relevance of several ice force characteristics observed from the ‘rigid’ structure tests to the ice-induced vibrations in the SDOF oscillators. The results from the rigid structure tests show that the median ice forcing frequency is linearly related to the ice drift speed. The mean and standard deviation of the ice forces on the rigid structure show a negative force-velocity gradient at low ice drift speeds and indications of a positive force-velocity gradient at higher ice drift speeds. The comparison of experimental results to the simulations of the single-degree-of-freedom oscillator tests shows that the positive force-velocity gradient at higher ice drift speeds allows to best capture the dynamics during continuous brittle crushing as observed in the experiments. Furthermore, the comparison shows that frequency lock-in initiation is primarily driven by the velocity-independent spatial frequency spectrum of the ice force signal. The added damping caused by the positive force-velocity gradient must be considered to capture the frequency lock-in initiation speeds measured in the constant deceleration experiments. The consideration of the negative force-velocity gradient at low relative velocities is not needed to capture these frequency lock-in initiation speeds as observed in the experiments. However, once frequency lock-in is initiated, the negative gradient is needed to correctly capture the dynamics during frequency lock-in. Analysis of the results shows that the peak forces during intermittent crushing at the end of the load build-up phase have a dependence on relative velocity equal to the load dependence on velocity of rigid structures at low speed. This indicates that intermittent crushing is not a purely brittle type of interaction.

这项研究分析了盆地试验的结果，其中垂直侧的圆柱形桩加载了冰在破碎中失败。使用“刚性”结构和代表一系列单自由度 (SDOF) 振荡器的结构模型进行了测试，这些振荡器涵盖了广泛的质量、频率和阻尼值。结构模型由实时混合测试装置表示，该装置结合物理和数值组件来测量真实的冰力，将力应用于数值结构模型，并实时模拟测试结构模型的动力学。对测试结果进行了分析，并进行了简单的数值模拟，以评估从“刚性”结构测试中观察到的几个冰力特性与单自由度振荡器中冰激振动的相关性。刚性结构试验结果表明，中值冰强迫频率与冰漂移速度呈线性相关。刚性结构上的冰力的平均值和标准偏差在冰漂移速度较低时显示出负的力-速度梯度，在冰漂移速度较高时显示出正的力-速度梯度。实验结果与单自由度振荡器测试模拟的比较表明，在较高的冰漂移速度下，正的力-速度梯度可以最好地捕捉实验中观察到的连续脆性破碎过程中的动力学。此外，比较表明频率锁定启动主要由冰力信号的与速度无关的空间频谱驱动。必须考虑由正力-速度梯度引起的附加阻尼，以捕获在恒定减速实验中测量的频率锁定起始速度。不需要考虑在低相对速度下的负力-速度梯度来捕捉实验中观察到的这些频率锁定起始速度。然而，一旦频率锁定开始，就需要负梯度来正确捕捉频率锁定期间的动态。对结果的分析表明，在载荷建立阶段结束时，间歇破碎期间的峰值力对相对速度的依赖性与载荷对低速刚性结构速度的依赖性相同。这表明间歇破碎不是纯粹的脆性相互作用。