基于频域内随机振动响应与载荷的关系，根据对结构控制点随机振动响应谱的预设，提出一种新的随机载荷谱简便识别方法。首先计算结构在白噪声载荷谱下，结构控制点处的响应功率谱，即系统的频响函数；然后将控制点的期望输出响应谱与控制点在白噪声载荷谱下的响应谱相比，进而得到相应的随机载荷谱。应用上述方法，借助于有限元仿真软件在设定控制点输出加速度响应谱为梯形谱的条件下，对某典型舱段结构进行基础加速度载荷谱逆向识别与正向检验，证明方法的有效性与准确性。%Based on the relationship between frequency response and load in the frequency domain and assuming the prior knowledge of the frequency response spectrum of random vibration at structural control points, a new method for identifying the random load spectrum was proposed. At first, the response power spectra at the structural control points, so-called as system frequency response function, were calculated. Then, the desired response spectra at the control points were compared with those under the white noise load spectrum input, and the corresponding random load spectrum was derived. Using this method, the results of the representative finite element simulation were presented based on the assumption that the output acceleration response spectrum at the control points was trapezoidal. The reverse identification and the regular correction of the fundamental acceleration load spectrum for a typical cabin structure verified the effectiveness and precision of this method.
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