VIBRATIONAL-ENERGY FLOWS IN-BEAM NETWORKS WITH COMPLIANT AND DISSIPATIVE JOINTS

Many structures and machines are made up from components (rods, beams and plates) which are joined together by welds, bolts or rivets. The m echanical behaviour of such built-up systems is greatly affected by th e properties of their joints which are usually compliant and dissipati ve. In this work, a general solution for the vibrational energy flows through a plane network of beams is sought, based on the receptance ap proach. The joints between any two elements are assumed to act at disc rete points and are modelled by three sets of springs and dashpots, th us being compliant and non-conservative in all the three degrees of fr eedom relevant to this case. The beams are assumed to be slender and e lastic, and the deflections at the joint are assumed to be small, so t hat conventional linear beam theory may be used in the analysis. The a im of this study is to give greater insight into the problem of non-co nservative coupling, which has not been extensively discussed in the l iterature. Interest is focused on the effect of damping in the joints on the magnitudes of energy flows between, and energy levels in, each beam. Variations in the energy flows through a compliant joint between two beams with changes in their coupling angle are also discussed. Nu merical examples which illustrate these various ideas are presented. ( C) 1997 Academic Press Limited.