ELASTOMERIC BEARINGS
PART 1 GENERAL
1.1SECTION INCLUDES
A.Plain elastomeric bearing pads.
B.Steel reinforced elastomeric bearing pads.
C.Components of elastomeric bearings such as masonry, sole and shim
plates, shear plates, anchor bolts, guide devices, and polytetrafluoroethylene (PTFE) surfacing.
1.2RELATED SECTIONS
A.Section 09972: Painting for Structural Steel
1.3REFERENCES
A.AASHTO M 251: Plain and Laminated Elastomeric Bridge Bearings
B.AASHTO M 270: Structural Steel for Bridges
C.AASHTO LRFD Bridge Design Specifications
D.AASHTO LRFD Bridge Construction Specifications
E.AASHTO/AWS D1.5: Bridge Welding Code
F.AASHTO/AWS D1.6: Structural Welding Code – Stainless Steel
G.ASTM A 240: Chromium and Chromium-Nickel Stainless Steel Plate,
Sheet, and Strip for Pressure Vessels and for General Applications
H.ASTM F 1554: Anchor Bolts, Steel, 36, 55, and 105-ksi Yield Strength
I.American Institute of Steel Construction (AISC)
1.4DEFINITIONS Not Used
Elastomeric Bearings
1.5SUBMITTALS
A.Working Drawings
1.Detailed shop drawings of fabricated materials for review. Include
at least the following, as applicable:
a.Total quantity of each type of bearing
b.Plan view and section view showing relative dimensions of
each type of bearing
c.The maximum design coefficient of friction for sliding
surfaces
d.Materials for bearing elements
e.Welding details for welding process used in bearing
manufacture
f.Vertical and horizontal load, rotation and movement capacity
g.Painting or coating requirements
h.Anchorage details
i.Location of fabrication plant
j.Manufacturer’s name and name of the representative
responsible for coordinating production, inspection, sampling and testing
2.Jacking Drawings for replacement elastomeric bearings for review
when applicable. Include at least the following:
a.Jack locations
b.Jacking sequence
c.Jack technical data
d.Temporary shoring
e.Bridge lift dimension and required jack extension
f.Dead loads and live loads
g.Provide supporting calculations with design to the AASHTO
LRFD Bridge Design Specifications, including at least the following: 1) Jacked bridge element analysis, such as diaphragm (member and local) and girder (local) analysis. 2) Jack supporting element analysis, such as concrete bearing strength and falsework analysis. 3) Temporary shoring.
h.Provide the seal of a PE or SE licensed in the State of Utah
on drawings and calculations
B.Materials
1.Certified Mill Test Reports (MTR) for steel materials for information
C.Manufacturer’s Certificate of Compliance for the elastomeric bearings.
1.Certify that each bearing satisfies the requirements of the contract
documents and the AASHTO LRFD Bridge Construction Specifications, Chapter 18. Elastomeric Bearings
2.Include the Polytetraflouroethylene (PTFE) coefficient of friction as
specified in this Section and AASHTO LRFD Bridge Construction Specifications, Article 18.1.5.2.3 where applicable. Include at least the following:
a.Corresponding lot numbers appearing on the shipping
package
b.Certification
c.Test location
d.Time and date
e.Results of testing
3.Include documentation of AISC certification. Refer to this Section,
Article 2.7.
D.Welding Procedures and Qualifications for review. Include at least the
following:
1.Weld Procedure Specifications and Procedure Qualification
Records as required by AASHTO/AWS D1.5.
2.Welder Qualification Record for each operator, process, and
position as required by AASHTO/AWS D1.5.
a.Include a letter or continuity log from the fabricator that
states the certified welders have been using the process without an interruption of more than six months since being certified.
PART 2 PRODUCTS
2.1ELASTOMERIC BEARING PAD
A.Refer to AASHTO M 251.
B.Satisfy the requirements of AASHTO LRFD Bridge Construction
Specifications, Section 18.
2.2STRUCTURAL STEEL
A.AASHTO M 270, Grade 36.
1.Paint non-weathering steel according to Section 09972.
2.3POLYTETRAFLUOROETHYLENE (PTFE)
A.Refer to AASHTO LRFD Bridge Construction Specifications, Section 18.
B.Use material composed of either filled or unfilled virgin PTFE sheets.
Elastomeric Bearings
C.Use a thickness of at least:
1.0.25 inch when maximum dimension of PTFE is greater than 24
inches
2.0.1875 inch otherwise
2.4STAINLESS STEEL PLATE
A.Refer to ASTM A 240, Type 304.
B.Use a thickness of at least 1/8 inch.
C.Provide a mirror-like finish of 8 micro inch or less (root mean square) on
the side that contacts the PTFE.
2.5ANCHOR BOLTS, WASHERS AND NUTS
A.Refer to ASTM F 1554, Grade 36, 55, or 105-ksi.
1.Provide Hot-Dip galvanized assemblies.
2.6MANUFACTURE
A Manufacture according to AASHTO LRFD Bridge Construction Specifications, Section 18.1.4 and AASHTO M 251.
1.AISC Highway Metal Components Certification (CPT) is required
for fabrication of metal bearing components.
B.Elastomeric bearings with sliding surfaces.
1.Recess and bond PTFE to top plate at manufacturer’s facility.
a.Recess at least one-half of PTFE thickness.
b.Do not bond the PTFE to the stainless steel sliding plate.
c.Make the bonded PTFE surface smooth and free from
bubbles.
d.Polish the filled PTFE surfaces.
2.Weld the stainless steel with ⅛ inch continuous fillet welds to the
sole plate.
a.Use a single piece of stainless steel.
b.Do not allow the weld metal to project beyond the plane of
the sliding surface.
c.Use welding procedures compatible with the stainless steel
specified. 1) Refer to AWS D1.6 Structural Welding Code – Stainless Steel.
d.Stainless steel sheet must be flat, free from wrinkles, and in
continuous contact with the sole plate after welding.
Elastomeric Bearings
3.Protect stainless steel and PTFE sliding surfaces during
manufacture, shipment, and erection.
a.Clean the sliding surfaces immediately before setting the
girder in place.
b.The Department considers the unit damaged when the
sliding surfaces are damaged by scratches, weld splatter, gouges, overspray from painting, and other defects.
4.Do not exceed coefficient of friction shown.
2.7TESTING
A.Test according to AASHTO LRFD Bridge Construction Specifications and
AASHTO M 251.
PART 3 EXECUTION
3.1INSTALLATION
A.Do not place bearings or structural steel bearing plates on bearing areas
that are improperly finished, deformed, or irregular.
1.Set bearings and bearing plates level with full even bearing.
B.Place bearings within 1/8 inch of position shown.
C.Orient bearings as shown.
1.Align bearings to within an angular tolerance of 0.02 radians
(1/4 inch per ft), except for guided bearings with sliding surfaces.
2.Guided bearings with sliding surfaces must align to within an
angular tolerance of 0.005 radians (1/16 inch per ft).
3.Place elastomeric bearings so that the identification markings are
visible after completion of the bridge.
D.Do not subject the elastomer or its bond to temperatures higher than 250
degrees F.
E.Do not epoxy bond or adhesively bond elastomeric bearing to concrete.
3.2REPLACEMENT ELASTOMERIC BEARINGS
A.Follow the authorized jacking drawings.
B.Remove existing bearings as shown.
END OF SECTION Elastomeric Bearings
Elastomeric Bearings in other states
Utah revises spec sections through supplementals and new editions. We check this one every week and email you the day it changes. Free, no account.
Source: Utah Standard Specifications for Road and Bridge Construction, 2026 Edition. Pages 1144–1148 of 1,331.
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