The aim of this study is to investigate the effects of the existence of a central hole on the main design parameters of a circular fiber-reinforced rubber bearing; namely compression modulus and shear strain due to compression. Since the compressive behavior of a multi-layered rubber bearing is mainly governed by the behavior of a single interior rubber layer in the bearing bonded to the reinforcing sheets at its top and bottom faces, the study is concentrated on uniformly compressed “bonded” rubber layers. The related compression problem is formulated using the “pressure” method. After deriving the closed-form expressions for compression modulus and shear strain, the effects of the hole on compressive behavior are investigated for fiber-reinforced bearings with different initial shape factors (a kind of aspect ratio for individual rubber layers) and rubber compressibility. It is shown that the compression modulus of a fiber-reinforced bearing may decrease considerably as the size of the central hole or the flexibility of the reinforcement increases, especially if the shape factor of the bearing is high and the compressibility of the rubber is not negligible. The study also shows that the effect of the hole on maximum shear strain reaches its most striking value when the hole size is smaller than 10% of the outer radius of the bearing.
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