Suspension Type Base Isolation: For Seismic Impact Mitigation in High-Rise Buildings

Abstract

Suspension Type Base Isolation (STBI) is a system where the base of a structure is literally suspended using suspenders. With STBI innovative design and construction, significant reduction in seismic impact could be achieved in all heights of structures from low-rise, mid-rise, to high-rise ones. The significant reduction in impact can be observed in reduced structure’s displacement, acceleration, and base shear of structure during earthquake events. The structural and mechanical design of the STBI is especially suited for high-rise structures. This new innovative system can handle uplift forces on columns caused by relatively large overturning moments in high-rise structures during seismic events. Most seismic isolators in use presently are not applicable for high-rise buildings. STBI is capable of mitigating seismic impact as could be observed in reduced structural displacement and acceleration by around 88% as compared to fixed-base structure even in strong earthquake events. Simply stated, if the earthquake intensity, for instance, is around 9, the structure will “feel” around intensity 5 only. Another ideal feature of STBI is its ability to allow the structure to sway back to its original position after every seismic event. This is called auto-centering which is initiated by the pull of gravity.