  In this study, an efficient reanalysis strategy for dynamic topology
optimization is proposed. Compared with other related studies, an online
successive dynamic reanalysis method and POD-based approximate dynamic
displacement strategy are integrated. In dynamic reanalysis, the storage of the
stiffness matrix decomposition can be avoided and the reduced basis vectors
should be updated successively according to the structural status in each
iteration. Therefore, the bottleneck of combined approximation method for
large-scale dynamic topology optimization can be handled. Sequentially, the
Proper Orthogonal Decomposition (POD) is employed to obtain the approximate
dynamic displacement, in which the Proper Orthogonal Mode (POM) of the
displacement field is employed to establish the approximated equivalent static
loads of Equivalent Static Load (ESL) method. Compared with the exact
equivalent static loads at all the time intervals, the number of equivalent
static loads is significantly reduced. Finally, the 2D and 3D test results
indicate that the proposed method has remarkable speed-up effect on the premise
of small relative error, support the strength of the proposed strategy.
