Hydraulic shock absorbers use fluids for converting mechanic energy of an earthquake in thermal energy. The process of absorption of energy is assisted by the shock absorber fluid, actuated by the piston and turned into mechanic force, which forces the passage of the fluid through the flow restrictor.
Seismic shock absorbers can be designed for linear and rotary damping. In other types of civil engineering applications they can be used for different movements, as well as in industrial and other fields of application.
Finally, huge hydraulic dampers are used in the field of structural engineering (buildings o critical industrial constructions) in order to reduce structural vulnerability of the constructions to the damages caused by seismic waves resonance.