UFC 3-270-07
12 August 2002
the matting unless there is adequate drainage. When this happens, water eventually
pumps through the matting and erodes the base.
2-4.2.4 Base Quality. Experience has shown that AM-2 performs best on a layer of
clean, well-graded, compacted crushed stone subbase. The amount of maintenance
required to care for this mat varies depending on the following factors: soil condition;
quality of the base and subbase; type of membrane used; weather; and the impact of
aircraft traffic.
2-4.2.5 Plastic Membrane. On a base of inferior silt or clay, AM-2 matting gives
much better service if a geomembrane is placed beneath the AM-2 surface. Although
the initial cost of geomembrane is high, it can be cost-effective for long-term operations.
2-4.2.6 Traffic. The most important step in prolonging the life of AM-2 that is laid
directly on a silt or clay base is to keep aircraft and vehicular traffic to an absolute
minimum during and following periods of inclement weather. This will allow water under
the surface to drain completely from the base; otherwise, the impact of the traffic will
pump the water into the base and destroy it.
2-4.2.7 Precautions in Repairing/Laying AM-2 Panels. Remember that AM-2 can
only be laid in one direction: right to left facing the direction in which the mat is placed.
Experience with AM-2 has shown the following:
2-4.2.7.1 It requires 200 to 300 percent more effort to place/install AM-2 than it does to
remove it.
2-4.2.7.2 The more perfect the finished grade of the base course, the easier it is to lay
AM-2.
2-4.2.7.3 Six hours is about the maximum time a person can sustain production when
handling AM-2. In the tropics, people can handle more matting in a six-hour night shift
than in a 10-hour shift in the heat of the day.
2-4.2.7.4 Use a string line along the edge for proper alignment.
2-4.2.7.5 To maintain proper alignment, always use a locking bar as a spacer behind
the last joint.
2-4.2.7.6 Never crowd the bundles of stacked panels next to the panels being laid, as
this may require moving the stacked bundles twice.
2-4.2.8
General AM-2 Assembly Guidelines
2-4.2.8.1 AM-2 matting can be assembled in place (taxiway and aprons) or assembled
away from the repair and towed into position (crater repair). Mats assembled in place
usually don't require all the ancillary pieces, like starter key lock, mandrels, or towing
tubes that a mat to be towed into place will require to keep it from separating during
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