Link points to Internet Archive / others. Not hosted by InfraLens. Details
IS 16644:2018 is the Indian Standard (BIS) for spherical and cylindrical bearings for bridges - specification. This standard specifies the requirements for materials, design, manufacturing, and testing of spherical and cylindrical bearings for bridges. It provides design values for PTFE, stainless steel, and other components, and details the acceptance criteria to ensure the bearings can accommodate translational and rotational movements under design loads.
Specifies material, design, manufacturing, testing, and acceptance requirements for spherical and cylindrical bearings used in bridges.
Overview
Status
Current
Usage level
Specialized
Domain
Structural Engineering — Bridges and Bridge Engineering
BIM-relevant code. See the BIM Hub for ISO 19650, IFC, and LOD/LOIN frameworks used alongside it.
Practical Notes
! Spherical bearings accommodate rotation about any horizontal axis, whereas cylindrical bearings permit rotation about a single axis only. This choice is critical and depends on the bridge's articulation scheme.
! Installation precision is paramount. Any misalignment or improper grouting can lead to eccentric loading, premature wear, and failure of the bearing.
! The design of the guidance system to resist horizontal forces is as important as the bearing itself and must be considered integrally with the bearing selection.
Section 14.7.4 covers the design and material requirements for spherical bearings within a broader bridge design code.
AS 5100.4:2017Standards Australia, Australia
HighCurrent
Bridge design - Part 4: Bearings and deck joints
Covers design, materials, and testing for various bridge bearings, including specific clauses for spherical bearings.
BS 5400-9:1983BSI (British Standards Institution), UK
MediumWithdrawn
Steel, concrete and composite bridges - Part 9: Bridge bearings
Provided rules for design and materials for various bearings, including spherical types, before harmonization with EN standards.
Key Differences
≠Material specifications for structural steel are based on national standards; IS 16644 references IS 2062, while EN 1337 references EN 10025, and AASHTO LRFD references relevant ASTM grades.
≠The methodology for calculating the coefficient of friction for PTFE surfaces differs. IS 16644 provides a formula based on pressure, temperature, and velocity, whereas AASHTO LRFD provides tabulated values, and EN 1337-2 provides its own set of formulas and tables.
≠Corrosion protection requirements are tailored to local environments and standards. IS 16644 specifies systems based on IS 13214, while EN 1337-9 specifies systems according to ISO 12944 for European conditions.
≠Prototype testing requirements vary. For example, IS 16644 specifies a test vertical load of 1.25 times the maximum design load, whereas EN 1337-1 requires 1.5 times the characteristic load.
Key Similarities
≈All standards are based on the same fundamental mechanical principle: using mating convex and concave surfaces to accommodate rotation and a flat sliding interface to accommodate translation.
≈The use of dimpled and lubricated Polytetrafluoroethylene (PTFE) sheets sliding against a polished stainless steel surface is the universally accepted industry standard for the translational element.
≈The definition and arrangement of key components (e.g., calotte, spherical plate, backing plates, sliding surfaces) are conceptually identical across all standards.
≈All standards mandate a combination of type testing (prototype approval), material certification, and factory production control to ensure the quality and performance of the manufactured bearings.
Parameter Comparison
Parameter
IS Value
International
Source
Max. design contact pressure on PTFE (dimpled, lubricated)
60 MPa
60 MPa (for Class B systems at T=-35°C)
EN 1337-2:2004
Minimum thickness of stainless steel sliding surface
1.5 mm
1.5 mm (0.06 inches)
AASHTO LRFD 2020
Minimum thickness of recessed PTFE sheet
5.0 mm
4.5 mm (for recess depth 2.25 mm, can vary)
EN 1337-2:2004
Maximum design coefficient of friction (lubricated PTFE)
~0.05 (Calculated via formula for a typical pressure of 30 MPa)
0.06 (Tabulated maximum value)
AASHTO LRFD 2020
Primary structural steel grade (example)
IS 2062 Gr. E250 BR/B0/C
EN 10025-2 Gr. S235JR/J0/J2
EN 1337-7:2004
Vertical load for prototype performance test
1.25 x max. design vertical load
1.5 x max. characteristic vertical load
EN 1337-1:2000
Surface roughness of stainless steel sheet (Ra)
≤ 0.2 μm
≤ 0.2 μm
AS 5100.4:2017
⚠ Verify details from original standards before use
Key Values6
Quick Reference Values
Maximum contact pressure on dimpled lubricated PTFE45 N/mm²
Minimum thickness of stainless steel sliding sheet1.5 mm
Characteristic coefficient of friction for dimpled PTFE0.03
Minimum projection of PTFE from its recess2.0 mm
Minimum ambient temperature for design (unless specified otherwise)-20 °C
Minimum hardness of stainless steel sheet130 HV10
Key Formulas
N_Sd / A_eff <= f_d,ptfe — Check for compressive stress on PTFE
μ_max = f_b * f_t * f_α * f_e — Calculation of maximum design coefficient of friction