Versiflex™ HLMR Pot and Disc Bearing Assemblies are high-load, low-profile bearings used for isolating and supporting heavy structures.
Answer: AASHTO section 14.6.1 states,“multi-rotational bearings conforming to the provisions of this section should not be used where vertical loads are less than 20 percent of the vertical bearing capacity.” Although it is not clearly stated, this should be considered at the service limit state (not the strength or extreme) as indicated by the fact that the wording is directly copied from the old ASD specifications. D.S. Brown’s understanding of this specification is that it is intended to avoid issues associated with simultaneous low-load and high-rotation. In this condition, the disc would not be fully compressed, and you could observe lift-off on one side of the disc. If it is severe enough, the piston could even disengage the pot wall, or disc bearing plate the shear pin. While it is good practice to avoid simultaneous low-load and high-rotation, design accommodations can be made on a case-by-case basis (beyond “the provisions of this section”) for such a condition, if needed. For more information, contact D.S. Brown.
Learn more about D.S. Brown Structural Bearing Assemblies
D.S. Brown is one of the leading suppliers of structural bearing assemblies.
Since 1963, The D.S. Brown Company has provided bearing assemblies and joint seals for bridges around the globe. Bridges and other large structures are supported on bearing assemblies to transmit forces while accommodating all structural movements.
The selection of an appropriate bearing assembly is based on the magnitude of vertical and horizontal forces transmitted through the bearing assembly, as well as the amount of displacement and rotation of the superstructure elements. In addition, special attention to the bearing assembly design may be necessary when, for example, larger than normal horizontal loading or uplift situations exist.
With extensive experience and utilizing the latest technologies, D.S. Brown can efficiently design, manufacture and test Versiflex™ high-load multi-rotational (Versiflex™ HLMR) pot and disc style, spherical, seismic isolation and elastomeric bearing assemblies for all types of construction.
D.S. Brown is available to work closely with bridge owners and engineering design consultants to assist in the design, selection and testing of the proper structural bearing assemblies.