2. The geosynthetic should be rolled, by hand, in line with the trail centerline
in one continuous sheet. This is best accomplished with two people, one on
each edge.
3. The geosynthetic should not be dragged across the subgrade surface.
4. Wrinkles and folds should be removed by stretching as required.
5. Overlapping is not recommended for these tests. However, if it is necessary,
a 1-m (3-ft) overlap is recommended and the previous roll should be on top.
6. For curves, the geosynthetic should be folded and overlapped in the direc-
tion of the turn (previous fabric on top).
Sections utilizing a geotextile separator
7. Before covering with material, the geotextile should be inspected for holes,
rips, and tears. If any occur, Karen Henry should be contacted in order to
make a decision about whether to replace, repair or proceed with no repairs.
8. The chunkwood, tire chips or slash should be end-dumped onto the geotextile
from the edges of it or from the previously placed material.
9. Lift thicknesses will be the same as those sections without the geotextile. (If
the soil is supersaturated, it may be necessary to limit the height of the pile
dumped in order to avoid failure of the subgrade.) At no time should the lift
thickness be thinner than the design lift thickness; thus, the lifts should be
graded down from a pile dumped near the edge or from a previously placed
lift.
10. If, after trafficking, grading is required due to excessive rutting, new mate-
rial should be added to the ruts in order to avoid damage to the geotextile
separator.
Bare geosynthetic sections
11. If problematic ruts form in the test section during construction (or traffick-
ing), the ruts (only) should be filled with fill that is available and deemed
suitable. In addition to filling in the ruts, this will help the material resist further
deformation into the ruts. Possibilities for fill include chunkwood, logs, aggregate
or tire chips. Alternatively, the material could be staked approximately every
meter (23 ft) near the edges if the thaw depth is not too shallow. However, this is
not the "first choice" since the material will be damaged by driving stakes
through it, and this will increase the chances of rips and tears propagating at these
locations.
WOODED TRAIL
For the wooded trail, the test sections will be laid out as shown in Figure F2.
Two construction crews can work simultaneously building toward the center area
containing the control test areas (one wet and one dry). The control areas should
not be trafficked or disturbed during the construction phase. The 3 wet areas on
the south end of the road are in a clearing and therefore these can be driven
around during construction in the woods to alleviate undue disturbance prior to
trafficking.
SLOPES
The test sections will be laid out as in Figure F3. The road grade should be
made as uniform as possible prior to building the test sections. This may
involve grading or bulldozing to cut high spots and fill low areas.
The test sections will be constructed in a similar manner as the test sections in
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