Partial Floor Mass Isolation to Control Seismic Stress in Framed Buildings

Partial Floor Mass Isolation to Control Seismic Stress in Framed Buildings

M.C. Porcu

Department of mechanical, Chemical and materials Engineering, University of Cagliari, Italy.

30 June 2019
| Citation



Isolating portions of the floor mass through rigid–plastic connectors may reduce the effects of strong earthquakes on framed buildings. This strategy was shown to be effective for single-storey frames, provided that a reasonably low plastic limit given to connectors and large enough portions of mass be disconnected. The stress reduction is however found to depend significantly on some interrelated parameters and on the given earthquake. By means of an analytical study and a nonlinear numerical investigation involving single-storey frames and four recorded earthquakes, the present paper gives a swift way to estimate the extent of stress reduction that can be achieved under a given earthquake, for preset values of the key parameters. Some empirical formulae are also provided to estimate the peak relative displacement that is reached by the disconnected mass.


Floor mass isolation, inertia limiters, rigid–plastic connectors, seismic stress control.


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