Variable curvature pendulum isolator and viscous fluid damper for seismic isolation of structures

The performance of a variable curvature pendulum isolator (VCPI) with additional passive damping using a viscous fluid damper (VFD) for seismic isolation of a structure is studied. VCPI is developed by varying the curvature of the conventional friction pendulum system (FPS). A four story symmetrical space frame structure isolated using VCPI with VFD is analysed to study the effectiveness of the proposed system. The performance of the VCPI is compared to a corresponding performance of a conventional FPS. The results of the analysis show that the proposed isolator reduces the base shear considerably without increase in the residual displacement. Further, a hybrid system consisting of VCPI and VFD is found to be more effective than a FPS and VFD hybrid system to isolate the structure subjected to the earthquake ground motions.