Rebutting is a proven process & technology that replaces the in-ground portion of a timber pole with a steel and concrete stub.

Poles are reinstated by lifting them clear of the ground and removing the degraded butt. (See illustration)

The lower section of the pole is then machined to the same diameter as the new galvanised stub. The caisson is then placed in the original hole and the machined section of the pole is lowered into it.

The pole is then straightened and the hole around the installation is back-filled and compacted.

Rebutting is usually also performed without interruption to customer supply, and the resulting fully Reinstated poles are stronger and more durable than a standard timber pole.

Adapt-A-Pole utilises two types of stubs, Caissons which are the most commonly utilised stub and  Sliding Sleeves for specialist applications.

Sliding Sleeves

Are suitable for all applications, however they do require a greater capital outlay and are generally only used for reinstatement when a pole cannot be moved e.g. because of an attached stay wire. These sliding stubs consist of a precast reinforced concrete butt over which a steel sleeve is fitted.

Poles are rebutted by digging a relief hole down beside the existing installation and extracting the old butt via the same hole. (See illustration)

The new stub is then positioned under the pole and the steel sleeve is then raised to neatly contain both the concrete butt and the machined section of the pole. The sleeve is then bolted in place, the pole straightened and the relief hole is back-filled and compacted.

Caissons

Our standard tube is the Caisson which consists of a full-length steel tube that is 3/4 filled with concrete. These tubes are used for both the construction of new composite poles, and of course for standard pole reinstatements.

Grab and Lift the Pole 1
Align the truck to the pole
Grab and Lift the Pole 1
Grab the pole
Lift the Pole
Lift the pole
Sling and remove the Butt
Sling the butt
Sling and remove the Butt
Remove the butt
align the cutter ring
Align the cutter ring
align the cutter ring
Align the cutter ring
Ensure hole depth
Ensure hole depth
Lower the tube
Lower the tube
Insert the pole into the tube
Insert the pole into the tube
Straighten and backfill the hole
Straighten and backfill the hole

Technical Information

Theoretical Bending Moments of rebutting Sleeves

References: Marks Engineers Handbook.Tubeline RHS & CHS Safe Load Tables for A1163 Grade C.350
Basis of calculations: Tube will fail in bending (extreme fibrestress). Other modes of failure are precluded due to fit of timber in tube (upper) and concrete poured in base.
Therefore : 8 = My / I = M / Z yield = 350 MPa
8 = StressM = Moment

y = Radius

I = Second Moment

My / I = Section Modulus

OD of Steel Tube (mm) Wall Thickness (mm) Z x 10^3 mm 3 Theoretical Bending Moment at yield (kNm)
219.1 6.4 221 77.35
273.1 6.4 349 122.15
323.9 6.4 497 173.95
355.6 6.4 602 210.7
406.4 6.4 792 277.15
457.0 6.4 929 325.15

 

AS/NZS 2878:2000 Timber – Classification into Strength Groups

S1 SD1 S2 SD2
Bending Strength MPa 103 150 86 130
Modulus of Elasticity MPa 16,300 21,500 14,200 18,500

 Download Strength Calculations Tables

Should extra strength be required a thicker walled tube can be used. ADAPT-A-POLE uses standard products which have published physical properties. Supplies of steel tube publish these lists of tube sizes with bending moments for each size shown.

Are you ready to improve your network & save millions at the same time?

CONTACT US TODAY