Bratu P., Nastac S.

This paper is part of the ample and complex approach developed by authors since 2002 and treats the antivibrating elastic systems behaviour considering the natural loads, like various types of harmful vibrating waves, seismic waves, shocks etc, particularly the case of the antivibrating elastic systems having polygonal shape. These innovative systems aim to isolate vibration and/or seismic waves and they incorporate rubber elastic elements, arranged as polygonal shape nodes and connected together by means of stiff elements. The main purpose of this elastic elements structure arrangement is to obtain very low values for the natural frequency of the entire ensemble: basement - isolation - structure. So the isolator must assure very large displacements under the dynamic loads. The proposed arrangement of the elastic elements aims to increase artificially the values of the elastic elements displacement. One very important step in the systems analysis, is represented by the experimental estimation of the dynamic behaviour, particularly the transmissibility and the isolation degree taking into consideration the actual state and marking out the practical working zone. The dynamic analysis has been developed for two types of elastic isolation systems (with six and eight elastic nodes). The tests have been carried out in laboratory simulating of the actual static and dynamic loads. This paper presents the experimental sets of the actual isolation characteristics obtained for the hexagonal and octagonal shapes of the antivibrating elastic system, as well as the results of the numerical simulation basing on the experimental tests. Analysing the diagrams, both the quantitative, and the qualitative aspects of the system dynamic behaviour and, especially, the isolation performances could be estimated. Besides the experimental results - obtained from static and dynamic tests, the information help to complete evaluation of these innovative and high performance antivibrating elastic systems.