[reference]
A. Charalampakis, G. Tsiatas, P. Tsopelas. 3DGRIPS - New rocking/rolling geared seismic isolation system for structures and equipment. 6th Panhellenic Conference on Seismic Engineering and Engineering Seismology (PSAMTS), 30/10-1/11/2025, Athens, Greece.
[abstract]
Seismic isolation is a proven effective seismic protection technique with numerous applications in real structures. In contrast to traditional methods of structural design, where strength is required to be greater than action, the application of seismic isolation leads to more economical and safer structures due to the reduction of seismic actions. Conventional methods of seismic isolation include elastomeric bearings, friction bearing (flat or spherical, FPS type), and systems based on rolling or rocking.
In this paper, a new rocking-rolling seismic isolation system is presented, which is primarily aimed at protecting objects of low weight and high importance, either due to their value (such as museum exhibits) or due to the requirement of uninterrupted operation in emergency conditions (such as servers, hospital and telecommunication equipment). The proposed system is differentiated from conventional rolling systems because it includes (a) a three-dimensional indentation on the contact surfaces to avoid slippage by increasing the damping, and (b) a flat contact surface in the resting state, which ensures a reduction of the developing stresses (since the loads are not transferred pointwise, but surfacewise) as well as a complete return to the initial equilibrium position after the seismic excitation. The proposed system is designed to avoid large deformations while, due to symmetry about the central axis, it can be easily manufactured in a lathe.
[paper]