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Spun Concrete Poles > Frequently Asked Questions
Click on any question to reveal the answer.
- Can Valmont-Newmark make multi-piece poles?
Yes, Valmont-Newmark has been making multi-piece, or splice, poles for years. A typical splice pole is comprised of two or more sections joined with our patented tubular steel splice joint. See
Splice Joint Concrete Poles for more information.
- Does Valmont-Newmark make wood pole equivalents?
Yes, Valmont-Newmark has been providing wood pole equivalents (WPE) since day one. We have WPE designs for both ANSI 05.1 (appendix B) and NESC (ANSI C2-1997) requirements.
- How do you ground a concrete pole?
Concrete poles can be grounded externally or internally. External grounding is usually provided by attaching the ground wire to the pole surface using ground clips and cast-in threaded inserts. Internal grounding is usually provided by casting the ground wire into the wall of the pole during fabrication. A threaded "tank ground," also cast into the pole during fabrication, then provides the external connection for hardware attachments.
- How do you pick up a concrete pole?
When handling a concrete pole in the horizontal position, it's usually best to lift it from two points of equal distance at either side of the center of gravity. All of Valmont-Newmark's concrete poles are marked with the recommended two-point pick-up locations. Using these locations for sling attachments will ensure trouble-free installation.
- What is a cracking moment?
Simply put, cracking moment is the bending moment required to induce visible cracking in the outer surface of the concrete. Cracking moment, referred to as Mcr, is a somewhat subjective capacity that must be verified by testing (which Valmont-Newmark has done extensively).
- What overload factors should be used for design of spun concrete poles?
Valmont-Newmark does not officially endorse or specify any particular overload factors. However, most of our customers use the National Electric Safety Code (NESC C2-1997) as a starting point for their loading criteria. Other guidelines can be found in:
- How do you field drill a spun concrete pole?
There are times when a structure may need additional holes after it is received in the field. Field drilling of prestressed concrete poles is fairly common. The task can be relatively simple and take minimal time provided proper equipment is used. A properly sized rotor hammer drill with a carbide-tipped bit is used to bore through one wall thickness of the pole. The drill is then repositioned 180 degrees, at the same elevation as the bored hole, to bore the other side of the pole; thus completing the pathway through the pole. If prestress strand is encountered, the hole is normally repositioned slightly away from the strand. The spiral wire can easily be drilled through by using the hammer mode on the drill. This process normally takes only a few minutes per side. Proper equipment should be used and aligned properly. Any exposed steel should be cleaned and coated prior to using the field drilled hole. Minor spalling of concrete is acceptable. Recently developed heavy duty core saw bits allow the user to drill through the prestressed stranded cable.
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