Comparison of the modal damping

Changes in modal damping of delaminated specimens are presented in comparison to the healthy laminate in percentage term in Figure 38.4(b).

Figure 38.4 (b) Change in modal damping with respect to the healthy laminate (0^o plies)

It is seen that the increase in modal damping in Delam Type-I is more prominent in comparison to Delam Type-II. Prominent increase in modal damping for all the modes except second bending mode is observed with respect to healthy laminate. Damping increase is nominal in second bending mode. It may be explained as the first case lies in a higher shear region (i.e. closer to the clamped end).

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