IS 785

: 1998

Reinforced Concrete Poles for Overhead Power and Telecommunication Lines

CurrentSpecializedSpecificationStructural Engineering · Cement Matrix Products
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This standard specifies the manufacturing, design, and testing requirements for solid and hollow reinforced concrete poles used in overhead power transmission and telecommunication lines. It provides guidelines on material selection, dimensional tolerances, clear cover, and mandatory transverse strength testing to ensure utility poles can safely withstand wind and line tension loads.

Reinforced Concrete Poles for Overhead Power and Telecommunication Lines

Quick Reference Values
Minimum clear cover (spun poles)15 mm
Minimum clear cover (mechanically compacted poles)20 mm
Tolerance on overall length± 15 mm
Tolerance on cross-sectional dimensions+ 5 mm, - 3 mm
Minimum curing period14 days
Transverse strength safety factor2.5 (typical working to ultimate)
Practical Notes
Ensure lifting hooks or holes are positioned strictly according to the design to avoid cracking during handling, transportation, and erection.
Proper curing is highly critical for poles due to their high surface-area-to-volume ratio and direct exposure to severe environmental conditions.
During the transverse load test, the pole must be rigidly fixed from the butt end up to the exact planting depth to accurately simulate field boundary conditions.