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C. Adam, A. Krakora:
"Shake table studies of elastic-plastic shear frames with secondary elements";
in: "Proceedings of 12th European Conference on Earthquake Engineering", issued by: 12th European Conference on Earthquake Engineering; Elsevier Science, Kidlington, 2002, ISBN: 0080440495, Paper ID 112, 10 pages.

Results from experimental studies of earthquake excited small-scale primary-secondary structures are presented. The primary structure considered is a plane three-storey shear frame with a fundamental frequency of 5.55 Hz. The columns of the second floor are built with soft aluminum and they are stressed beyond its linear range of behavior. The elastic-plastic shear frame is tested with and without an attached secondary structure. The secondary structure is modeled as an elastic SDOF oscillator, and its natural frequency is tuned to the fundamental frequency of the shear frame. Alternatively, the oscillator is mounted on the horizontal beam of the first and third floor. The base excitation of the structural model is characterized by a broad band random process. In comparative numerical studies the digital recorded acceleration of the base excites the mechanical model of the investigated structures. Numerical outcomes assuming fictitious unlimited elastic material behavior of the shear frame are set in contrast to results from experiments and computational simulations where the measured non-linear force displacement relation of the elastic-plastic floor is approximated by a piecewise linear curve. The effect of elastic-plastic materials on the dynamic interaction between primary and secondary structure is shown and the difference to unlimited elastic material behavior is worked out in detail.