Bumper device and its material

[nikaul]

Hi I am searching for a bumper device that can be use in building which can gradually increase stiffness and also can recover (meaning no damage) during the impact cycles during earthquake.

 

[JAE]

Are you talking about structural isolators that are installed at the base of the building columns?

 

[nikaul]

It is to be use in the friction device and not at the base of building. Actually I am looking for a material for bumper which can take force without any/some deformation.
Thanks.