The Roball
A new seismic isolation device
DOI:
https://doi.org/10.5459/bnzsee.35.3.204-207Abstract
Robinson Seismic's latest developments in seismic isolation includes a new device, the RoballTM, for seismically isolating structures during earthquakes.
This advance is a new concept for seismic isolation based on the principle of the inverted pendulum. It consists of 'friction balls' or 'Roballs' moving between upper and lower spherical like cavities or flat plates. The Roballs are filled with a material which is able to provide the friction forces required to absorb the energy from numerous earthquakes while supporting the structure. The Roball technique is expected to enable light and in the future possibly heavy structures to be more economically seismically isolated.
As part of a program to develop a user friendly 'seismic isolation system' a series of full-scale tests have been carried out on a number of possible designs including three approaches for vertical pressures of -1 MPa resulting in coefficients of friction of -0.1 to -0.4.
In this paper we present the preliminary experimental results.
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