Hysteretic Dampers with mechanical bearings

The device is a combination of a mechanical bearing to carry the vertical load and a hysteretic elasto-plastic damper capable of controlling the horizontal force level and to dissipate energy due to the earthquake.
The  devices fulfill the following requirements:

Transmit the vertical loads due to permanent and accidental effects;

Allow the rotation between the structure and the infrastructures up to 0.01 rad

Allow, with very low reaction the parasite reaction due to structure length variations due to creep, shrinkage and thermal effects

Transmit the horizontal service load with small movements remaining with elastic response behavior

In the case of significant earthquakes limit the reaction force and dissipate energy by hysteretic behavior

Guarantee a stable response characteristic during a dynamic response with no cycle deterioration

The  devices assure the following advantages:

- Very simple maintenance equal to the standard POT and spherical bearing because all the structural parts made by steel

- Possibility of controlling the horizontal force transmitted from the superstructure to the substructure

- Reaction characteristic very simple (bilinear), stable with no temperature dependence

- After a catastrophic earthquake only the elements that dissipate energy by yielding must be replaced with no damage to other components of the structure