432 BEARINGS

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432.01 DESCRIPTION.
Furnish and install bearings fabricated per Section 430. Perform welding per AWSAmerican Welding Society D1.5.
432.02 MATERIALS.
Steel Plates       909.02
Bronze or Copper Alloy Bearing and Expansion Plates       910.01
Elastomeric Bearing Pads       910.02
Preformed Fabric Pads       910.02.03
Epoxy Adhesives       921.04
432.03 CONSTRUCTION.
432.03.01 Storage and Handling. Store all types of bearings at the site under cover and on suitable blocking or platform at least 4 in. above all types of surfaces and vegetation. Protect from damage at all times and, when placed, keep them dry, clean, free of dirt, oil, grease, and other foreign substances.
432.03.02 Installation. Place preformed fabric pad on surfaces meeting 420.03.07(c) prior to installing the masonry bearing plate.
Ensure that all bearings and pedestals of truss, stringer spans, and the center and end bearing of swing spans are rigidly and permanently located to correct alignments and elevations.
Refer to the applicable portions of Section 430 for the attachment of bearings or plates to steel superstructures.
432.03.03 Steel, Bronze, or Copper Bearings. When steel, bronze, or copper alloy bearings are specified, thoroughly clean the machined bearing surfaces immediately before installation. As soon as practicable after installation, apply one prime coat to all unpainted exposed surfaces of the bearings scheduled for painting. Then proceed with the application of the specified field coats.
432.03.04 Elastomeric Bearing Pads. Prior to installation, give the pads and abutting surfaces a final cleaning to ensure that they are free of dust, dirt, oil, grease, moisture, and other foreign substances. Use an approved solvent that is compatible with the adhesive prior to application of the epoxy adhesive. Mix and apply the epoxy adhesive according to the manufacturer’s recommendations.
When elastomeric pads are used without masonry bearing plates, grind the masonry bearing surfaces to remove all laitance before applying the adhesive. Apply the adhesive to the surfaces of the masonry bearing areas that will be in contact with the bearing pads and to the full contact area of the bearing pad. After the pads are in place, use blocking or other approved mechanical methods to secure the pads in their final position until the adhesive sets.
Surface temperatures and predicted ambient air temperature for the next four hours shall be 50 F or higher at the time of application unless otherwise specified or recommended by the epoxy adhesive manufacturer and approved.
432.04 MEASUREMENT AND PAYMENT.
Bearings will not be measured but the cost will be incidental to other pertinent items specified.