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Lightweight-focused design often leads to a problematic vibration susceptibility of designed components. To reduce potential environmental and health risks, excessive vibrations have to be mitigated preferably through lightweight-compatible solutions. The presented studies aim at the establishment of almost weight-neutral solutions for adaptive tuning of the dynamic behaviour of lightweight components. The proposed unique actuating principle is based on structural cavities generating evanescent deformations when supplied with fluidic medium. These cavities encapsulate compressible, viscoelastic elements which are combined with the surrounding layers and operate according to an extended principle of Constrained Layer Damping. The evanescent morphing is used to deliberately alter the geometrical and material properties of the viscoelastic elements through their compression in order to achieve a damping and stiffness capacity adaptation. The analysed Compressible Constrained Layer Damping (CCLD) object is configured as a three layered beam consisting of the load-bearing structure as well as constraining layer and compressible viscoelastic layer. The main studies were conducted using a developed finite-element model. Herein, the geometrical, material and load property range has been parametrised so that generalised conclusions about the CCLD dynamic behaviour could be drawn. The deformation kinematics of the CCLD under combined loads resulting from static tension and flexural vibrations has been analysed. Furthermore, the assessment of the dynamic behaviour adaptation potential for different compressible viscoelastic materials was carried out. The goal of this study was on the one hand to determine a feasible initial configuration of the CCLD for its successful application and on the other hand the assessment of its damping efficiency.

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The rapidly developing market for high strength and high stiffness carbon fibre-reinforced composites demands among others for reliable damage evaluation methods for very high cycle fatigue loading (VHCF). For the analysis of the widely unknown damage behaviour at VHCF loading specific test principles and a shaker based fatigue test stand are developed. Key requirements herein are: high frequency fatigue (f > 150 Hz) without significant warming of the specimen, homogeneous stress distribution and minor through thickness stress gradients as well as adjustable mean stresses for the fatigue testing regarding specific failure modes. Using numerical and experimental investigations a promising solution for the given problem has been found in form of a shear force free bending test stand and a specifically layered specimen.