Discussion on Using Phase-frequency Curve to Solve the Dynamic Parameters of the Model Foundation

Through the combination of forward theory derivation and data inverse verification, the method for solving the dynamic parameters of the model foundation is obtained by using the amplitude-frequency response curve and phase-frequency response curve before peak frequency. It is pointed out that the theoretical amplitude-frequency curve and phase-frequency curve are reversed by the dynamic parameters solved by the above method, and if the theoretical curve is close to the measured curve, it can be shown that the dynamic parameters obtained by solving can represent the dynamic characteristics of the measured vibration system of the foundation soil and the model foundation. If the theoretical curve deviates from the measured curve, the correctness of the calculation method and the representativeness of the data value should be checked. It is pointed out that even if the disturbance frequency of the exciter can cover the resonance frequency, it is also of great significance to measure the vibration amplitude and obtain the amplitude-frequency curve while monitoring the phase difference between the excitation and response, and obtaining the phase frequency curve. Using the regressive reflection photoelectric switch and automatic test instrument, the phase difference between the excitation force and the vibration displacement can be easily measured, and the amplitude-frequency curve and the phase frequency curve can be displayed synchronously during the test.