An analysis of the relationship shown in Figure 8a shows that the damping of P2 monolithic slabs and composite slabs, which have not been destroyed by delamination, is approximately constant. It means that in case of slabs P3, P5, the existence of a concrete connection does not affect vibration damping. In the case of slabs the destruction of which is accompanied by delamination (P4 and P6) after applying QII force, damping was increased with increasing amplitude. This means that the presence of a joint of two concretes in those slabs influenced the damping.