Robin StevensTeam Leader Track Design Queensland Rail
Infrastructure location and Drainage
• Common Sense
• Bigger Picture Overview
• Working Together
• There is no substitute for correct turnout location & construction in attaining high long term reliability.
• It is almost impossible to rectify poor design and construction via maintenance processes
• Compared with other trackside or infrastructure equipment, points failures will invariably account for the greatest delays to train operations, therefore location, drainage and accessibility is critical.
• Basic Renewals
– Need
– Integration with other works
– Transition opportunity
– Correct existing deficiencies
– Review current performance issues
– Operational improvements
– Technological improvements
• Greenfield Sites for Turnouts
– Eliminate Horizontal curvatures
– No Vertical Curves
– Formation & Drainage
– Clearances
– Access
Result of turnout on a curve
• Vehicular Access
– Permit a suitable hiab truck or crane to travel safely to the turnout
– Access road should be weather resistant and suitable for heavy vehicles
– Permit a hiab truck or crane to unload
– Permit a hiab truck or crane to turn around
– Allowance to pass other structures
The cess is not wide
enough to permit
vehicular access to
the turnout.
Small vehicles, in this
case, can get close to
the turnout. Larger
vehicles or crane
trucks can not.
Access
Suitable access permits a hiab
truck to access adjacent to the
turnout, allowing new and old
material to be loaded directly onto
the track, thereby reducing manual
handling, time and resources
Well Designed Access
Track Access is Critical for the
Installation & Maintenance of Infrastructure
Walkway material has
been spread along the
track covering the
components and
preventing normal
inspections
Walkway material has been
spread over the ballast and
will eventually cause
ballast/formation failure by
preventing water to escape.
Driver Walkways
Note the walkway permits,
for the mechanised tamping
of the track
Driver Walkways
Safe Operation of Points
Level area for stable footing
when operating manual
lever
• Drainage
– Loss of vertical geometry
– Loss of horizontal geometry
– Formation of “bog holes” and track pumping
– Sleeper/Bearer failure
– Rail breaks
– Derailment
Drainage
Turnout located on top
of embankment
Drainage
DrainageEmbankment
slippage
Blocked cess
drains
Embankment
erosion
Poor
drainage
resulting in
fouled ballast
and sleeper
pumping
• Catchpoints used to intentionally derail a train
rather than let it cross onto another track
– Fitted at end of
• Yards
• Loops
• Refuges
• Junctions
• Catchpoints comprise a single switch and
stockrail assembly, ramp block and throw-off
rail.
Ramp block
Switch assemblyThrow-off rail
Ramp block
Switch assemblyThrow-off rail
• Catchpoints design must include
– Safe landing area
– Clearance from main line
– Account for:• Train type
• Train speed
• Risk to both infrastructure and personnel
• Catchpoint with safe landing area
Run out area shall provide
clearance to all structures and be
a minimum of two vehicles in
length
Catchpoint Landing Area
Catchpoint with Insufficient Landing Area
Catchpoints
• Catchpoints with unsafe landing area
Catchpoints & Structures
Catchpoints
Catchpoint Derailment
Case Study
?
• Common Sense
• Bigger Picture Overview
• Designers on sites
• Working Together to
Achieve the Best Result