A Laminated elastomeric bearing is an elastomeric rubber block reinforced with steel plates vulcanised when built. This bearing is the connection between a structure and its support, and should make the following possible through elastic deformation:
- transmission of normal forces
- horizontal movements
- rotation of the structure in any direction
- transmission of horizontal forces, within defined limits.It may also be provided with a sliding plane for withstanding large movements of the structure and also having a one or two horizontal movement locking systems
The 20th century witnessed the arrival of reinforced concrete and, in particular, the arrival of prestressed concrete whose rapid development after the second world war allowed the construction of structures which became more and more slender. The large movements in these structures brought about the introduction on the market of bearing devices which made use of the deformability characteristics of rubber.
It was from 1952 onwards, and thanks to one of Eugene Freyssinet’s ideas of combining rubber and metal in a single product, that the use of laminated elastomeric pads as structural bearing devices came into general use.
Initially consisting of superimposed layers of elastomer and sheets of tin-coated steel mesh, these bearing devices rapidly achieved the form in which they are used today: associating steel plates bonded to natural rubber or polychloroprene by vulcanization.
However, the progress achieved since this invention in the fabrication process and like of the constituent materials, and also in the generalized use of national regulations related to elastomeric bearings based upon the principles which were expounded by Eugene Freyssinet at an early date, has led to the presence on the market of products which are similar in their principle but with different characteristics.
This variety is present in the production and most of the bearings complying with national or international standards can be offered without design delays, while all individual specifications can be examined and satisfied.