VRIOGS 012.2.1 - Public Transport Victoria

38 VRIOGS 012.2.1 REVISION A
SECTION 14.0 CABLE PITS, CABLE JOINTING PITS AND CABLE
TURNING CHAMBERS
14.1 Cable Pits and Chambers
a) Pits and chambers shall be installed with the top at ground level, clear of roads and
pathways and shall remain within the property line of the VicTrack Rail Reserve.
Communications pits may be found outside the rail reserve, depending on the
network design.
b) The alignment of square pits and chambers shall be parallel to the property line.
c) The size and depth of pits and chambers shall be calculated to accommodate the
particular cable route requirements, access requirements for cable installation and
cable jointing activities. The internal size of all pits and cable turning chambers shall
provide for the minimum bending radius of the largest cable to be installed in them
d) Pit and chamber entries and exits shall be kept to a minimal size. All sharp edges
and burrs shall be removed to prevent cable damage. All cable entries into pits and
cable turning chambers shall have large radius rounded edges to prevent damage to
cables during installation and to eliminate the danger of cables bearing on sharp
corners or edges after installation.
e) Pits and chambers shall not be installed any closer than 3 metres from the outside
edge of the closest running rail; unless otherwise approved by the Infrastructure
Manager.
f) The end of conduits shall not protrude more than 50 mm into the pit space.
g) Conduits are to enter the ends of pits unless site conditions restrict the space to the
extent where that is not possible. Entries through the sides of pits are problematic
with optical fibre cable due to the higher minimum bending radius required. Approval
should be sought from the Infrastructure Manager (and the VicTrack Network
Maintenance Manager where relevant) before conduits and pits are installed. Long
radius bends should be used at pit entries.
h) Pits and chambers installed in open areas shall be protected on two diagonal
corners by white painted rail post (or an agreed alternative structure) to prevent
damage by vehicles. If there is a joint in a pit then the associated protection posts
are to be painted yellow.
i) Buried cables shall access a pit or chamber via 100 mm or suitable size conduits
that extend a minimum 2 metres from the outside entry point. Entry holes shall be
100 mm minimum from the base of the pit or chamber. All conduits are to enter from
the ends of pits and not from under the pit.
j) The exterior entry points for conduits into pits shall be sealed by a mortar compound
(ratio 4:1 sand/cement) or both externally and internally using an approved,
expanding silicone or similar based type sealant.
k) Ground Level Troughing shall rest on a bed of “A” grade 20 mm crushed rock or
clean fill 150 mm in depth for approximately 4 metres before opening into the pit or
chamber.
l) All pits associated with GST to equipment box interface shall have minimum
dimensions of 600 mm x 600 mm as shown on Drawing No. 112000/14/3.
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.