The purpose of using steel plates for elastomeric bearing

Elastomeric bearings are made of layers of synthetic chloroprene rubber (CR) or natural rubber (NR). Steel plates are placed between rubber layers, rubber layer will be merged by vulcanization to produce a single pad. The elastomeric bearing will allow for rotation of superstructure. Movement of the superstructure will be accommodated through elastic deformation.

Steel plates are embedded inside the elastomeric bearing to increase the stiffness of bearing. The bearing will undergo lateral bulging to resist the compression load. In the absence of steel plates. The bearing will deform largely, and the compressive resistance will be limited. Therefore, steel plates are inserted to increase the bearing compressive stiffness and to reduce the lateral bulging, as shown in figure 2. Tensile stresses are induced in these steel plates during their action in limiting the bulging of the elastomer. This, in turn, would limit the thickness of the steel plates. Shear stiffness will not be affected by the presence of steel plates. 

Figure 2

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