TY - CPAPER AU - Leutenegger, Tobias AU - Schlums, Dirk H. AU - Dual, Jürg T1 - Structural testing of fatigued structures T2 - Smart Structures and Materials 1999: Smart Structures and Integrated Systems ED - Wereley, Norman M. PY - 1999 L2 - http://proceedings.spiedigitallibrary.org/proceeding.aspx?articleid=982238 SP - 987 EP - 997 T3 - SPIE Proceedings AB - The structural responses of beams and tubes is investigated in theory and experiment in order to locate and assess damage in the form of fatigue cracks. Crack length measurements are performed in transversely vibrating beams by determining the resonant frequency, which is stabilized through a phase locked loop. Cracks are initiated and propagate from the notch of the structure which is vibrating at resonance. The frequency in relation to the crack length is modeled including the nonlinearity effect due to closing of the crack. Fatigue tests were also carried out with piezoelectrically excited microstructures. TS - CrossRef DO - 10.1117/12.350775 C7 - 1999 Symposium on Smart Structures and Materials C1 - Newport Beach, 1. März M4 - Citavi ER -