Substructuring is the topic of the Society of Experimental Mechanics’ Technical Division on Dynamic Substructures. During a number of the most recent IMAC conferences, a lot of studies of coupling and de-coupling of substructures have been presented. In addition, frequency response-, modal- and state-space based techniques for coupling of components represented by numerical or experimental models have been developed. In many such studies, the dynamics of the numerically coupled structures are compared with test data stemming from measurements of the physically assembled counterparts.

An embedded issue when assembling components is the interfacing between the substructures, introducing dry friction in the form of micro slip and varying contact areas. These introduced sources of deviation between the numerically formed assembly and its real world counterpart blend with sources, of deviation, such that test data being incomplete, biased or having random errors.

Here, the initial test object is manufactured as a one piece solid structure. After that, the structure will be cut to form two substructures. Finally, the substructures will be assembled again. Vibrational tests will be made on the solid structure, the substructures as well as on the assembly. The aim is to compare vibrational data and differences in dynamical properties; especially damping, eigenfrequencies and linearity between the solid structures, the numerically formed assembled and the physical re-assembled structure are studied. The purpose of the study is to isolate the causes of possibly deviations by removing the issues stemming from unknown interfaces. Here, the structure together with synthetic modes are presented.