The high-frequency response of a plate carrying a concentrated mass/spring system

The high-frequency response of a plate carrying a concentrated mass/spring system under random forces has been studied. An approximate expression for the local response of the concentrated mass relative to the plate and the inertial displacement of the spring end at its point of connection with the plate has been developed as the asymptotic limit of a classical component modal analysis by using Asymptotic Modal Analysis (AMA). It is shown that when the number of plate modes in the frequency bandwidth is sufficiently large, the AMA result is quite accurate. An exceptional case occurs when the natural frequency of the mass/spring system is inside the bandwidth interval of excitation. (C) 1998 Academic Press Limited.