Slot cutting fibre into carriageway? Who has done it?

edited February 2012 in General
I seem to remember being told that one local authority are achieving its UTMC comms network by slot cutting its fibre into the cariageway.

This is something i'm interested in and would love to speak to them.

Does anyone know anymore or have any contacts?


  • That sounds like a REALLY bad idea
  • Care to expand your response?
  • I'm afraid that I agree with Doug. As I understand it (although my experience of Fibre is limited) you cannot 'joint' fibre. Every time your road gets a pot hole repaired, the edge haunched, resurfaced or a utility company in, if the fibre is damaged you will have to replace the entire length. If the works that damage your cable last longer than a day, you could be without comms for however long they are there for and longer still if you can't then get road space booked.

    We are still trying to get away from 'gutter-cut' loops because of the amount of times they get damaged and the cost to replace. If you are losing part of your UTMC network each time, even worse.
  • Chris,

    You are wrong. You can join fibre just fine. There are some very clever splicing machines that are common practise these days. They even splice pre made connectors on to speed up termination.

    So as long as you looped in and out of a duct box every 200m or so you would limit the amount you had to repalce.
  • I can understand the attraction of this method as a temporary solution to a comms problem but surely the long term saving would be in installing ducting. Also (my knowledge is patchy) isnt there some loss with every splice / connector and if you have a long run with splices every 200m in duct boxes that would be quite a bit of loss? Surely 200m of slot cutting would take a while - how much is the TM going to cost each time you need to do this? Is there a particular reason that you want to avoid installing ducting?
  • Sorry, when I commented before I meant that you can't joint the cable as a 'running repair', the way you can with SWA for example.

    Even with 200m hops, if this is part of your strategic UTMC network, it seems very vulnerable to damage. It depends on how important it is to you to have it operational of course but I would have thought that the downtime for any outage while it is repaired, combined with the cost would be prohibitive.
  • Although not for UTC, we have two diverse backbone fibre links for our data centre slot cut in the carriageway.

    If I remember rightly, they are cut between 175 and 220mm deep, a 25mm tube installed through which the fibres are blown.

    I remain to be convinced by it in the long term, particularly where carriageway renewals are concerned (perhaps a case for lowering and putting in proper ducts in that case can be made?) or indeed utuilities works. And quite how the 25mm tube would stand up to compaction of new material around it...

    But its HAUC approved so its gotta be okay... right?
Sign In or Register to comment.

Welcome to the forum

Please sign in or register. You don't need to be an IHE member to take part.