What is the main manufacturing process for these poles?

The centrifugal spinning process, which involves casting concrete in a rotating mould (Clause 6).

What is the primary performance test for these poles?

The transverse load test, where the pole must sustain a specified working load without cracking and an ultimate load without failure (Clause 10.3).

What is the minimum grade of concrete required?

M40 grade concrete (Clause 4.3).

Are cracks allowed during the load test?

No visible cracks are permitted up to the stage of application of the specified working load (Clause 10.3.4).

IS 13158

: 1991

Prestressed concrete circular spun poles for overhead power, traction and telecommunication lines

CurrentSpecializedSpecificationBIMStructural Engineering · Cement Matrix Products

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This standard specifies the requirements for prestressed concrete (PSC) circular poles manufactured by the centrifugal spinning method. It covers materials, dimensions, manufacturing processes, testing procedures, and acceptance criteria for poles used in overhead power, traction, and telecommunication lines.

Prestressed concrete circular spun poles for overhead power, traction and telecommunication lines

Quick Reference Values

Minimum grade of concreteM 40

Minimum cement content360 kg/m³

Minimum cover to prestressing steel20 mm

Load factor for ultimate load test2.5 times the specified working load

Permissible deflection at working loadNot specified, but recovery of 85% of deflection is required after load removal

Permissible crack width at working loadNo visible cracks

Practical Notes

The centrifugal spinning process creates a dense, high-strength concrete outer layer, which enhances durability, but requires stringent quality control during production.

Handling and transportation of these slender poles require special care and specified support points to avoid damage before installation.

Verification of the transverse load test results is the most critical acceptance criterion for ensuring the pole's performance in service.