ANTISEISMIC DEVICES
ELASTOMERIC ISOLATORS WITH LEAD CORE
The ISI-P series ELASTOMERIC ISOLATORS consist of alternating rubber layers and reinforcing metal sheets with the insertion of a lead central core.
• G=0.40 MPA (Soft compound),
• G =0.80 MPA (Normal compound),
• G =1.40 MPA (Hard compound).
The internal steel blades ensure the containment of the device, thus counteracting excessive warping under load.
The rubber and steel layers are connected to each other by a vulcanisation process.
The lead core allows the device to achieve damping levels of up to 30%.
The devices are completed with external plates of adequate thickness to connect them to the structure.
ELASTOPLASTIC BEARINGS
Devices with nonlinear behaviour (NDL) in displacement dependent steel are metal retainers, which use the hysteretic properties of the material to dissipate energy. They consist of a series of steel elements designed to deform plastically under seismic action.
The RED type, made with crescent moon elements has a unidirectional configuration, so it acts in a single horizontal direction.
The AIOS type is a combination of fixed elastomeric disc bearings and hysteretic steel elements. The ‘C’ shaped steel elements acting as dissipators, may be placed in one horizontal direction only or in both, thus providing the device with unidirectional or bidirectional behaviour.
Hysteretic dissipative bracing is often used for retrofitting and seismic improvement of existing buildings, applying passive protection to the building that increases the strength and rigidity of the structure.
