The Multangular-Pyramid Concave Friction System (MPCFS) for seismic isolation: A preliminary numerical study

The Multangular Pyramid Concave Friction System (MPCFS) is introduced in this study. Different from the conventional Curved Surface Slider (CSS), the concavity of the MPCFS is designed as a multangular (mostly triangular or rectangular) pyramid, and the slider is removed from the isolator. While maintaining the virtues of the CFS, the MPCFS can provide greater vertical sustaining capacity with a more stable friction force. When combined with a cross uplift restraint, the MPCFS offers numerous virtues such as increased uplift stability, a greater initial yielding force, and resonance-dodge ability during near-fault earthquakes (variable frequency). Frequency-sweeping and acceleration time-history numerical investigations are conducted on a four-storey building model using the MPCFS. The revised State-Space Method (SSM) is expanded from two-degrees-of-freedom to multi-degrees-of-freedom as to accommodate more complex analysis such as dynamic analysis of high-rise, multi-storey structure installed with MPCFS. The simulation result verifies the merits of the MPCFS, indicating that the MPCFS, viewed as a beneficial complement to the existing well-established isolation techniques, may be a promising tool for the seismic isolation of high-rise, and super high-rise buildings in near-fault earthquake prone zones.