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Part II of this paper is focused on the dynamic response of a steel plate of the centrifuge model which is fixed on the container. This plate is 5 cm thick, allowing for non-destructive elastic response to all the 19 blasts. Three accelerators and 10 sets of strain gauges are installed on the plate to monitor the acceleration and deformation histories induced by shock waves and bubble oscillations. This article presents the characteristic values measured for shock waves and bubble oscillations response. The detailed information can be found in a database available on the web. In order to obtain the correct acceleration time history, the cut-off frequency of low-pass filtering by Fourier transformation was applied. The results indicated that the acceleration and strain induced by shock wave was nearly unaffected by the increasing gravity, while the effect of gravity has remarkable influence on those induced by bubble oscillation. A preliminary study of comparing the measured dynamic response with numerical simulations has been carried out using ANSYS LS-DYNA. The results captured the dynamic response in terms of characteristics and trends, but deviated in magnitude due the theoretical and technological limitations involved in both the physical and numerical models. It certainly deserves further studies.

Centrifuge is a promising tool for underwater explosion (UNDEX) research as both Mach and Froude similitudes could be satisfied with hyper-gravity in models, which would result in similarities in both shock wave and bubble oscillation. Scaling laws for UNDEX in centrifuge have been proposed based on dimensional analysis. Two dimensionless numbers, i.e., π3 and π4, are used to characterize shock wave and bubble oscillation, respectively. To validate scaling laws, 17 UNDEX tests are designed by varying accelerations or explosive weights and positions in centrifuge. The tests are classified into different groups to validate scaling laws as well as calibrate coefficients in empirical formulae for both shock wave and bubble oscillation. The results show that changes of gravity acceleration or hydrodynamic pressure almost has no influence on shock wave peak pressure and time constant as long as π3 is constant. The dimensionless bubble period and maximum radius agreed with each other when π4 is constant. Based on the research, an example is exhibited to suggest method for the computation of initial loading conditions for a submerged obstacle subjected to UNDEX.