A new formulation for the analysis of bonded elastic layers

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2007
Pınarbaşı, Seval
Elastic layers bonded to reinforcing sheets are widely used in many engineering applications, e.g., as elastic foundations to machinery, as seismic isolators to structures, etc. Because of its practical importance, the behavior of bonded elastic layers under some basic deformation modes (e.g., compression, bending and shear modes) has attracted the attention of many researchers. However, the analytical works available in literature involve, with the object of obtaining design formulas, many simplifying assumptions. In this dissertation, a new formulation is developed for the analysis of bonded elastic layers, which removes most of the assumptions used in the earlier formulations. Since the displacement boundary conditions are included in the formulation itself, there is no need to start the formulation with some assumptions on stress and/or displacement distributions or with some limitations on geometrical and/or material properties. For this reason, the solutions derived from this formulation are valid not only for “thin” layers of strictly/nearly incompressible materials but also for “thick” layers and/or compressible materials. The advanced solutions obtained within the framework of the new formulation are used to study the behavior of bonded elastic layers under basic deformation modes. The effects of three key parameters, shape factor, Poisson’s ratio and reinforcement flexibility, on effective layer moduli, displacement/stress distributions, and location/magnitude of maximum stresses are investigated. It is shown that the stress assumptions of the “pressure” method are inconsistent with the results obtained for thick layers and/or compressible materials and/or flexible reinforcements, and that the assumption “plane sections remain plane” is not valid, in general.

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Citation Formats
S. Pınarbaşı, “A new formulation for the analysis of bonded elastic layers,” Ph.D. - Doctoral Program, Middle East Technical University, 2007.