ABSTRACT
Within the last decade developments in building base isolation have resulted in this technique being applied in practice to reduce seismic-induced forces, notwithstanding the fact that some aspects of bearing behavior are understood only imperfectly leading to very conservative bearing designs. In this paper the principles of seismic base isolation are reviewed, several approaches to the provision of practical isolation systems are outlined, the design aspects of two specific applications are summarized, and ongoing efforts to examine theoretically the axial load capacity of elastomeric bearings at high shear strains are described. It is anticipated that the availability of improved mathematical models of these bearings will allow designers to achieve more efficient and reliable isolation systems in the future.
