February_2022 - 17

Vancouver, B.C.
looking at how to make that more
efficient and more responsive. "
Toward that end, SkyTrain
is currently planning to replace
its in-house grinders. Increased
in-house capacity will enable
BCRTC to advance its preventative
grind program and balance
grinding capacity with future line
extensions on the horizon.
Noise: A condition
indicator
With the rail surface condition
well in hand, BCRTC was able
to direct energy and resources
toward another high-priority,
high-profile issue - one that all
rail transit systems face to varying
degrees: noise. Specifically, wheel/
rail-generated noise.
As a system that operates primarily
on an elevated guideway
near businesses and densely populated
residential communities in
Vancouver's packed urban environment,
noise is a genuine problem.
And controlling it is a real
challenge. But having successfully
addressed one formidable challenge,
the BCRTC engineering/
maintenance team rolled up their
sleeves to tackle another.
" Arresting wear and degradation
was our problem, but we've
moved beyond that, " Doyle said.
" Noise is now our priority. "
" We don't just want to mask
noise or put a band-aid on the
problem, " Vesik added. " We want
to address the root cause. "
BCRTC determined that addressing
- and ultimately reducing
- wheel/rail-generated
noise, which can exceed 90 decibels
(dBA) on some parts the system,
would not only benefit riders
and neighbors near the tracks, it
could also serve as a bellwether
of improving or degrading track
conditions, since noise can be an
indicator of track condition.
" Although noise isn't necessarily
a direct indicator of poor
condition, we can use noise and
impact vibration to home in on
locations that may require maintenance, "
Vesik said. " We can also
look at the assets in these locations
to see if we need to improve the
materials, like using harder rail
or a friction modifier, to reduce
corrugation and increase the interval
required for maintenance. "
While viewing asset management
through a noise lens can be
effective from a maintenance perspective,
it also makes sense from
a business perspective, Vesik says.
" Controlling noise helps improve
the state of good repair
and extends asset
life. Looked
at the other way, improving the
state of good repair will likely
improve ride quality and reduce
noise and the number of residents'
complaints, " he explained.
" If we can control the noise to
acceptable levels, " Doyle added,
" we can be confident that the system
is in a state of good repair. "
Since SkyTrain is not regulated
by the U.S. Federal Transit Administration,
BCRTC refers to a
state of good repair as an engineering
standard, rather than a
legal or regulatory standard.
" Our goal is 100 percent asset
performance when performing
scheduled maintenance and being
able to predict the end of the
useful life of an asset and having
a plan to replace it, " Vesik said.
With that in mind, TransLink
commissioned a study in 2018
to assess noise on the SkyTrain
system and recommend ways to
deal with it. The initial report
recommended looking into the
feasibility and effectiveness of six
noise-mitigation measures:
* Improvements to switch maintenance
practices
* Investigation of harder rail steel
* Re-introduction of friction modifiers
to improve long-term rail
condition
* Improvements to rail grinding
practices
* Installation of rail dampers to reduce
noise radiated from the rails
* Development of guidelines for
new residential developments
near SkyTrain
TransLink
GRINDING FACETS on a freshly ground rail. Marking
on the rail indicates the future contact patch for
reference by the Corrugation Analyzer Trolley.
FEBRUARY 2022 | MassTransitmag.com | Mass Transit | 17
TransLink
RAIL DAMPERS installed in areas prone to corrugation
have been shown to reduce noise by up to six dBA.
Jack Lindquist
A PROFILE template is used to determine how
closely the rail profile matches the target profile.
http://www.MassTransitmag.com
February_2022

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