and could potentially expose construction per-
necessary for most cases. Anchoring techniques
sonnel to enemy fire. Like tire chips, it is not a
require further development.
desirable surface for small rubber-tired vehicle
passage or foot traffic; walking is extremely diffi-
Techniques used in combination
cult. Tree slash can also puncture and damage
Each of the above techniques serves some por-
hydraulic hoses on the underside of equipment.
tion of the design function, and combinations of
methods often proved to be more effective than
any individual method.
Prefabricated large
wood mats (Uni-Mats)
Although tank cornering was not tested on Uni-
LITERATURE CITED
Mats during this demonstration project, its suc-
cess in cornering on relatively level terrain has
Alkire, B.D., and L. Winters (1986) Soil strength
been documented elsewhere. Uni-Mats seem to
recovery using a Clegg impact device. In Proceed-
be the only surface that can withstand the trauma
ings of the Fourth International Conference on Cold
of tank tracks undergoing cornering. They are not
Regions Engineering, Anchorage, Alaska, February.
designed for bridging large ruts and were slip-
Arola, R., R.J. Hodek, J.K. Bowman, and G.B.
pery on slopes particularly when wet. Uni-Mats
Schulze (1991) Forest roads built with chunkwood
are extremely heavy and require specialized equip-
from chunkwood: Production, characterization and
ment for placement.
utilization. North Central Experiment Station,
USDA Forest Service, General Technical Report
NC-145, St. Paul, Minnesota, June.
Small portable wood pallets
Constructing these on site requires time and
ASTM (1985) ASTM D2216 Method for labora-
labor. However, ease of placement for the effec-
tory determination of water (moisture) content of
tiveness of performance is a plus. Lumber is typi-
soil, rock, and soil-aggregate mixtures. Annual Book
cally available almost anywhere and is inexpen-
of ASTM Standards, Vol. 04.08.
sive. Mats were broken during tank trafficking,
Clegg, B. (1978) An impact soil test for low cost
but they continued to performed well (stabilized
roads. In Proceedings of 2nd Conference of Road En-
a weak thawing soil to adequately support traf-
gineers Association of Asia and Australia, Manila,
ficking). A strong species of wood is necessary if
October.
re-use is expected; however, this can double the
Englund, E., and A. Sparks (1992) Geostatistical
cost of the pallets.
Environmental Assessment Software: GEO-EAS
Version 1.2.1. U.S. Environmental Protection
Agency, Las Vegas, Nevada, July.
Tire mats
Tire mats performed very well except for tank
Giroud, J.-P., and L. Noiray (1981) Geotextile-
cornering. Placement requires heavy equipment.
reinforced unpaved road design. In Proceedings of
For expediency, a lighter mat would be easier to
ASCE Journal of the Geotechnical Engineering Divi-
handle.
sion. Vol. 107, No. GT9.
Harr, M.E. (1991) Accounting for uncertainties in
pavement response. In 2nd International Sympo-
PVC fascine
No special equipment was required, and the
sium on State of the Art Pavement Response Monitor-
fascine mats could be constructed on site. For this
ing Systems for Roads and Airfield Pavements, West
demonstration, we decided to save on materials
Lebanon, New Hampshire, September.
by having a full mat (contiguous pipes) for the
Houston, S.L., W.N. Houston, and T. Anderson
tire tracks (wheel paths) with gaps between wheel
(1995) Moisture and strength variability in some
paths. The pipes partially silted in impeding wa-
Arizona subgrades. Transportation Research Board
ter flow through them. However, they provided a
Paper No. 950324.
stabilized surface.
Humphrey, D.N., and R.A. Eaton (1995) Thermal
properties of tire chips for use as insulation to
limit frost penetration beneath unpaved roads. In
Geosynthetics
All geosynthetics were placed quickly and with
74th Annual Transportation Research Board Meeting,
minimal labor. They are lightweight and easy to
Washington, D.C., January.
handle compared to the other surfaces. If un-
Isaaks, E.H., and R.M. Strivastava (1989) An Intro-
surfaced, geosynthetics can become entangled in
duction to Applied Geostatistics. Oxford: University
tank tracks. Cover improves performance and was
Press.
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