Download or read book Effect of Shape Factor on the Seismic Performance of Elastomeric Bearings written by Adam Talmage Neill and published by . This book was released on 2002 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt: Elastomeric bearings are increasingly becoming a design standard in the seismic isolation of large structures and buildings. The rubber bearings used in these designs are made of alternating layers of vulcanized natural or synthetic rubber and thin steel plates. These bearings are expensive to manufacture and are not applicable to smaller structures such as residential buildings. The idea of using inexpensive scrap-rubber tires for making base isolators for residential buildings has been proposed, but the performance of these bearings under seismic forces is not known. Shape factor is an aspect ratio term that is used in describing an elastomeric bearing's dimensional characteristics. Investigation into the performance of bearings with large shape factors has been extensive, but the performance of bearings with small shape factors has not been characterized. Theoretical modeling techniques employed for describing the behavior of rubber bearings with large shape factors are analyzed for the performance of bearings with small shape factors. Deflections of bearings with large shape factors are dominated by shear. As a bearing's shape factor decreases, the governing factor for the deflection changes from shear to bending. As the behavior of the bearing changes from shear to bending, different modeling techniques are necessary to analyze the system. The shape factor at which a bearing goes from shear to bending was established to be in the range of 0.15 to 0.30, which correlates well with theoretical predictions. It was additionally found that the theoretical modeling technique, used to describe the behavior of rubber in compression, is not adequate in predicting the performance of elastomeric bearings with small shape factors.