Using an existing plag pole base foundation for new pole

[arh13p]

I have an existing 80' steel flag pole. 14" at the base and tapers to 3.5" at the top. The base of the pole is encased in an 8' deep sleeve, 18" dia. with 2" bank sand filling around the pipe. The base is encased in concrete and the pedastal is granite with a granite platform and steps around it(20' diameter). The pole needs to be replaced and was wondering if re-using the base is practical. It appears the wedges could be removed and the pole removed. I was thinking water jetting and vacuum truck could get the sand cleaned out of the sleeve and a new pole installed with a new grounding apparatus. Has anyone done this or have any suggestions. I was hoping to reclaim the granite and have the final product look as it did, just a new pole. Thanks!

 

[racookpe1978]

I don't have any good background on the pole foundation itself, and will defer to other's experience.

Be careful though with the trucks or bobcats and construction loads on the 20 foot dia decorative granite. The crane loads and heavy wheel traffic will crack the granite easily. Keep the crane and its support jacks well off of the granite. Same with concrete trucks if you refill the holes.

 

[TLHS]

Assuming the loading works, you could also just cut the existing pole and splice on to it somehow.

 

[TLHS]

For example, cut it as close to the ground as you can while still having weld clearance and weld on the new base plate. You could frame a little pedestal or something to hide the splice if you aren't happy with the look of it.

 

[oldrunner]

That foundation seems to be a standard generic foundation. An 8 foot deep pipe for an 80 foot pole is 10% of the depth. Cleaning out the sand appears to be appropriate. I assume that you will be putting the same size pole back in. There is a specification for flag poles that you might be able to download - I think that it will show similar foundations.

 

[archeng59]

This might help you evaluate the foundation: Metal Flagpole Manual. Small fee to download.

http://www.scribd.com/doc/72015621/Metal-Flagpole-Manual-1980.

 

[oldrunner]

Yes that is the manual I was trying to remember. Apparently it is being revised and not available on the NAAMM website.

http://www.naamm.org/amp/amp_technical_literature.aspx

Page 14 - Foundation Details show an embedded type foundation, called a ground-set flagpole. There are guidelines for foundation depths and other details. We note that besides the 4 hardwood wedges shown, the there should be "Waterproof compound 2" deep above the wedges". This is to keep water from entering the "tamped dry sand". Make sure that you check that the 4 steel centering wedges at the bottom of the pipe (per the detail) are not damaged. Might send a GoPro camera down the hole to inspect the condition of these wedges. They are supposed to be welded to the pipe (which may be a corrugated steel tube).

I suggest that you obtain this publication. Note that there are some recommendations that you should be aware of.

Good luck.

 

[arh13p]

Thanks, I did download the publication and it appears the foundation is constructed like it is needed to be. My biggest thing is that I don't want to dig up the entire existing foundation and construct a new one, I was hoping to use what is there and just replace the pole. One option I am considering is cutting the pipe off and sliding the new pole right inside the old one. Based on my as-built dwg's and specifications on a new pipe, it should fit giving me about 1.6 inches for the sand filling. Anyone ever try this? Thanks.

 

[oldrunner]

Whoops! Unless the foundation pipe sleeve is really deteriorated, then I don't know why you wouldn't use the existing foundation. I thought the whole point was to replace a damaged or corroded or something existing flagpole with a new one. Is there some sort of distress in the existing foundation? I don't think that a smaller pipe inside an existing stub section will be adequate if you are using the same height. Why don't you talk to Tom Jordan at US Flag and Flagpole in Texas (409 658-9550). I've done large amount of poles for him and he is extremely knowledgeable.

 

[TLHS]

Tamping an inch and a half of sand would be pretty hard. For a gap that tight I'd probably grout it. You'd want to make sure your method of filling the gap ensures you don't get voids.