Will concrete damage a phone cable?

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Mike61

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#243754 30-Dec-2018 11:10

Long story short - digging a hole for a pergola post and 50mm down is the black telephone cable from street. If I dig hole carefully and then concrete the post in will the concrete cause any damage to the cable? I mean by a chemical reaction to the black sheath rather than abrasion.

Cheers

DarthKermit

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Trusted

#2152174 30-Dec-2018 11:22

It shouldn't do, but to be safe you could always put some kind of impervious barrier in the hole to keep the concrete away from the cable.

Aredwood

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#2152177 30-Dec-2018 11:23

The black plastic is most likely Polyethylene, Concrete won't affect it from a chemical reaction point of view.

I still don't like the idea of casting the cable into concrete though. Can you get a piece of 20mm or so PVC pipe, cut it lengthways, then clip it over the phone cable. To allow for movement in the cable and / or any future repairs. Note that the concrete and the cable will have different expansion rates in relation to temperature changes. So some movement is unavoidable.

Mike61

109 posts

Master Geek
+1 received by user: 28

#2152179 30-Dec-2018 11:28

Cheers, I'll see if I can put some sort of ducting around the cable or I might just dig that hole deeper and only concrete to within 100mm of the surface then fill with dirt.