Alternative scheme for frequency response function measurement of experimental-analytical dynamic substructuring

Abstract

The accuracy of the predicted dynamic behaviour of an assembled structure using the frequency based substructuring (FBS) method is often found to be diverged from the experimental counterparts. The divergence which has become the paramount concern and major issue for structural dynamicists is because of the unreliable experimental FRF data of the interfaces of substructures, arising from the limited resources of appropriate excitation points and accelerometer attachments in the vicinity of the interfaces. This paper presents an alternative scheme for FRF measurement of the experimental FRF data of substructures. In this study, an assembled structure consisting of two substructures were used, namely substructure A (Finite element model) and substructure B (Experimental model). The FE model of substructure A was constructed by using 3D elements and the FRFs were derived via the FRF synthesis method. Specially customised bolts were used to allow the attachment of accelerometers and excitation to be made at the interfaces of substructure B, and the FRFs were measured by using impact testing. Both substructures A and B were then coupled by using the FBS method and the coupled FRF was validated with the measured FRF counterparts. This work revealed that the proposed scheme with specially customized bolts has led to a significant enhancement and improvement in the FBS predicted results.

Representation of bolted joints in a structure using finite element modelling and model updating

“…In this work, the bolted joint structure was set-up for the experiment, as shown in Figure 5. The EMA procedure and setup were adopted based on the previous similar studies done by other researchers [29][30][31]. The bolted joint structure was assembled by joining two equally dimensional steel plates named as Plate A and Plate B with stainless steel bolts and nuts.…”

Micromechanical modeling of ductile fracture of human humerus

“…Their advantage lies mainly in the diversity of configurations and loading conditions and hence the optimization of time and the total benchmark cost. However, one can observe that the material constitutive laws used are often derived from the experimental characterizations carried out at the macroscopic scale ignoring the bone microarchitecture [4]. A micromechanical approach is more interesting to improve the limitations of these models [5].…”