[RE-wrenches] Pole Mounts - Frost/Conduit & Ledge

[Darryl Thayer]

I have done this 18 to 24" below grade conduit and our frost is 4 to 5 feet I 
have seen it freeze to 11 feet, I have not had a problem.  I have in clay areas 
seen telephone poles pushed out of the ground.  

dt





________________________________
From: Glenn Burt <glenn.burt at glbcc.com>
To: RE-wrenches <re-wrenches at lists.re-wrenches.org>
Sent: Sat, April 16, 2011 10:30:48 AM
Subject: Re: [RE-wrenches] Pole Mounts - Frost/Conduit & Ledge


1)      When we use this option, we bring the PVC conduit into the Sonotube 
below frost level.
2)      We had a similar situation & after consulting with an engineer, widened 
the form at the top, just below the ground according to his calculations – 
turned out almost to be a patio. Then they were buried. So I recommend finding 
an engineer to evaluate the TPM requirements and adapt a foundation to an 
equivalent.
Good Luck!
Glenn Burt
 
From:re-wrenches-bounces at lists.re-wrenches.org 
[mailto:re-wrenches-bounces at lists.re-wrenches.org] On Behalf Of Rich Nicol
Sent: Saturday, April 16, 2011 10:55 AM
To: re-wrenches at lists.re-wrenches.org
Subject: [RE-wrenches] Pole Mounts - Frost/Conduit & Ledge
 
Hi RE-Wrenches
1.      When installing pole mounts I have been running conduit into the side of 
the foundation and up the pole prior to pouring concrete.  The conduit enters 
the foundation ~ 18” to 24” below grade level.  We live in an area where frost 
depths are around 48” deep.  I have been told by folks in the construction 
industry that frost will not be problem with the conduit entry but I remain 
concerned that the conduit may be lifted, while the foundation which runs to 
below the frost depth, remains stationary thereby breaking the conduit.  Any 
insights?
 
2.      Secondly, does anyone have experience with ledge in respect to pole 
mounts.  I know the answer is to consult an engineer, but I thought I would 
bring it up to the experienced folks in the trade first.  I have two mounts 
scheduled for this spring where I expect to hit ledge.  The first is a TPM with 
six 230 watt modules and the second is with eight 230 watt modules.  I’m 
expecting ledge to be relatively close to grade level, perhaps around 12 to 24” 
deep.  Ledge in these locations is solid (generally granite, sometimes gneiss or 
basalt).  My initial thought is to form a larger rectangular foundation with 
pins drilled at 45 deg angles into the ledge and tied to the reinforcing within 
the foundation.  A wide base on the pole would then be bolted to the 
foundation.  Any recommendations?
 
Thanks
Rich
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org/attachments/20110416/1b3297bb/attachment-0004.html>