Geosynthetics February/March 2023 - 22

Innovative solution for ballast fouling
and manufactures multiple geosynthetic
products utilized in heavy construction
and rail applications. For this specific
issue, Industrial Fabrics, Inc. identified
its BaseLok line of products, which
includes geocell, geogrids and laminated
geogrids. Industrial Fabrics, Inc. was in
the process of developing a new product
to address ballast fouling with one
of its key partners. Texas City Terminal
Railway Company agreed to try this new
product, which initiated installation of a
test section in May 2021.
FIGURE 2 Severe ballast fouling along a seawall
at the Port of Texas City prior to installation of
BaseLok® BallastGuard™ - May 2021.
Photo courtesy of Al Florez
What exactly is ballast fouling?
Ballast fouling occurs when ballast
becomes contaminated with fines and
other deleterious material. Ballast is the
aggregate directly beneath the railroad
ties and rail. It is a rock material that is
most often between 0.75 inches and 3
inches in diameter. This relative gradation
allows for free drainage of water and
notable structural integrity. " This range
of particle-size is desirable for railroad
track because it offers high strength and
stiffness due to the high frictional resistance
between ballast rock particles "
(Bruzek et al. 2016). Interestingly, no
federal standard or specification exists
on ballast type or gradation. The Track
Safety Standards (TSS) lists minimum
track safety requirements. It is not considered
a standard for design; rather, it
is simply an inspection standard (Bruzek
et al. 2016). The ballast safety standard
found in §213.103 of the TSS (USDOT
2022) states:
Unless it is otherwise structurally supported,
all track shall be supported by
material which will-
* Transmit and distribute the load of
the track and railroad rolling equipment
to the subgrade;
* Restrain the track laterally, longitudinally,
and vertically under dynamic
loads imposed by railroad rolling
equipment and thermal stress exerted
by the rail;
* Provide adequate drainage for the
track; and
* Maintain proper track crosslevel, surface,
and alinement.
If fines or a high percentage of
smaller particles are present, the integrity
of the ballast and, therefore, these safety
standards are compromised. This presence
of contaminating small particles or
fine material is generally referred to as
ballast fouling.
Attempting to formulate a standard
FIGURE 3 Severe ballast fouling on a site in Ohio - November 2022.
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Geosynthetics | February March 2023
definition, Bruzek et al. (2016) identify
and discuss several methods of quantifying
ballast fouling. The Percent Passing
Method attempts to quantify fouling
material by equating percent fouling to
percent passing of a certain sieve. There
is no standard accepted sieve size, as
some countries define fouling material
as percent passing the No. 200 sieve
while others use percent passing the
1-inch sieve.
Geosynthetics February/March 2023

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