VRIOGS 012.2.1 - Public Transport Victoria

26 VRIOGS 012.2.1 REVISION A
not be used.
d) All attachment bolts shall have self locking nuts.
e) Troughing brackets shall have resilient rubber mountings installed to prevent
vibration damage.
f) Concrete bridges and viaducts shall not be drilled unless prior written approval has
been given by the Infrastructure Manager.
g) GST shall be made continuous by the use of joining sleeves. Jointing may be
welded, sleeved and bolted or riveted. Bolts or rivet heads shall be installed from the
inside of the trough to prevent damage to cables.
h) GST lids shall have galvanised chains welded between the lids and the troughing,
and as a minimum three (3) chains per lid with chain being a minimum diameter of
six (6) mm and a length of 200 mm each chain.
i) Under no circumstance shall troughing obstruct access to staff refuge recesses on
bridges and viaducts or in tunnels.
8.3 Wall Mounted Troughing
a) In tunnels, on platform faces and retaining walls where clearance is limited, the
minimum distance above rail level shall be 300 mm, but when restrictions apply due
to clearances, the troughing may be at rail level, and subject to approval by the
Infrastructure Manager.
b) No steel surfaces shall be installed directly on soil and GLT shall be utilised if
troughing is to be installed at ground level.
c) All troughing shall be made continuous by use of joining sleeves, and these sleeves
installed midpoint between the trunking supports.
d) Maximum height for mounting troughing shall be 1800 mm above rail level.
e) Support bracket intervals shall not exceed 3 metres.
f) Support brackets shall be secured to walls and rock faces by using masonry
anchors or other suitable fixing devices, maintaining a straight line. Mounting to
structural elements shall be submitted for approval of the Infrastructure Manager.
g) There shall be a minimum clearance of 25 mm between trough and the mounting
surface.
h) If the required clearance cannot be obtained using standard size troughing in a
limited clearance area, then slimline cable troughs or alternative methods of
securing cables may be considered subject to approval by the Infrastructure
Manager.
8.4 GST Over Culverts and Small Water Courses
a) In situations when the typical route of crossing bridges, culverts or water courses
(cables direct buried or installed within buried steel conduits) is not practical, bridges
may be constructed by using steel rails or other approved means to support the
steel troughing. The support structure shall be wide enough to carry the required
number of troughs and be sufficiently rigid to avoid undue deflection by the weight of
troughing, cables and foreign bodies up to 100 kg.
b) All troughing shall be made continuous by use of metal joining sleeves.
c) The troughing installation shall not impede the flow of water. Supports should be
positioned on the edge of the waterway and not in the centre of the flow.
d) The troughing lids shall have three (3) chains welded between each lid and
troughing, with chains installed as defined within this Standard.
NOTE: This document is controlled only when viewed on the DOT Engineering Standards website.
Any other copy of this document is uncontrolled, and the content may be inaccurate.