This standard specifies the requirements for materials, design, manufacturing, testing, supply, and installation of elastomeric bearings. These bearings are used for accommodating translations and rotations in bridges and other structures.
Specifies material, design, manufacturing, testing, and acceptance requirements for elastomeric bearings used in bridges.
Quick Reference Values
Elastomer Hardness (Shore A)55 ± 5
Minimum Tensile Strength (MPa)17
Minimum Ultimate Elongation (%)400
Maximum Compression Set (24h @ 70°C) (%)35
Design Shear Strain Limit0.7
Maximum average compressive stress (MPa)10
Key Formulas
S = (L * W) / (2 * ti * (L + W)) — Shape factor for rectangular bearing
σc = F / (A) ≤ 10 MPa — Check for average compressive stress
γs = Vs / Tr ≤ 0.7 — Check for shear strain
Practical Notes
Ensure strict adherence to installation tolerances, especially levelness and alignment, as improper installation is a major cause of premature bearing failure.
The bond between elastomer and steel laminates is critical. Visual inspection for delamination and the adhesion strength test (Clause 9.5) are crucial for quality assurance.
The design and material selection must account for the specific temperature range, seismic zone, and exposure conditions of the bridge site.