VRIOGS 012.2.1 - Public Transport Victoria

40 VRIOGS 012.2.1 REVISION A
chamber. Pits and chambers in areas of clay, rocks and other areas where excess
water run-off and similar are encountered; shall each have a drainage system in
place to cater for the excess water condition, and where identified necessary shall
further have a sump and associated drainage system installed. These may include
installing drainage conduits to the nearest approved railway drain or to a public
stormwater drain or natural drainage course, where possible.
b) If no suitable drains exist, or where impracticable to achieve a sump and drainage
system, then a gravel drainage sump or conduit to the side of an embankment shall
be installed. Gravel drainage sumps shall consist of 20 mm aggregate with a
minimum depth of 300 mm.
14.4 Types of Pits and Turning Chambers
Construction of pits and chambers shall conform to one of the following types, and shall
be Infrastructure Manager approved;
a) Reinforced fibreglass AS3572
b) Reinforced concrete chamber AS3600
c) Polyethylene conduit AS4130, class 3 minimum for depths to 1200 mm
d) High density polyethylene pit Telecom approved AS3900;
e) Precast concrete conduit AS4058, class Y or class Z
f) Precast Concrete
g) Concrete block
14.5 Cast on Site type Pits
a) Cast in situ concrete pits and cable turning chambers less than or equal to 1500 mm
deep shall be constructed with a minimum wall thickness of 100 mm with a layer of
F82 galvanised mesh reinforcement. The reinforcement shall be located to provide a
minimum cover of 50 mm from the outside of the wall.
b) Cast in situ concrete pits and cable turning chambers deeper than 1,500mm shall be
constructed with a minimum wall thickness of 150 mm with two layers of F62
galvanised mesh reinforcement. The reinforcement shall have a cover of 50 mm.
c) Pits and cable turning chambers constructed from concrete block shall include
appropriate steel reinforcement.
14.6 Pit and Chamber Covers and Collars:
a) Covers shall be labelled “RAILWAYS SIGNALS & COMMUNICATIONS” on their
outer surface. This label must be durable and weatherproof. Where pits are installed
in trafficable areas; the pit should be identified by an approved cable marker post in
close proximity to the pit, and with a label identifying cable pit offsets and services
installed within the pit.
b) Pit covers for general use shall be either commercial standard concrete composition
pit covers or 6 mm mild steel checker plate fitted with a security chain and lifting
handles. All parts shall be galvanised.
c) Light duty Gatic type pre-filled type pit covers or similar Infrastructure Manager
approved pit cover shall be used for pedestrian footways and platforms. The precast
collar to be constructed around Gatic covers shall have a thickness of 120 mm.
Backfill shall be compacted and level with the collar and surrounds.
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.