Surface Armor for Erosion Protection
7.4.5 USED-TIRE MATTRESS
7.4.5.1 Description
Used-tire mattress consists of tires fastened together with bands, cable or rope.
Whole tires are normally used, but tires sliced in half or tires with pieces removed are
sometimes available.
7.4.5.2 Advantages
Tires are often available at low cost, and use of tires in erosion control may be more
environmentally sound than landfill disposal. A tire mattress is conducive to the establishment
of woody vegetation.
7.4.5.3 Disadvantages
No formal guidance is available for determining limits of hydraulic forces. A tire
mattress is not suitable for severe conditions unless an underlayment and multiple layers of
tires are used, which negates the cost advantage. Vulnerability to hydraulic forces, vandalism,
and theft is greatest immediately after construction, before exposed areas become vegetated.
Environmental regulations may prohibit the use of tires in many areas. Also, a tire
mattress is not aesthetic, although if site conditions permit heavy vegetative growth and
deposition of sediment, the appearance improves with time.
7.4.5.4 Design Considerations
To combat vandalism and theft, and to reduce buoyancy during high flows, if whole
tires are used, then one or more of the following measures should be employed:
Stout and durable synthetic or galvanized connections;
Backfilling with earth over the completed revetment; and
Cutting or burning a hole in the upper sidewall of each tire.
Less durable connections can be used if the quick establishment of woody vegetation
is certain, and vandalism is not expected to be a problem. However, the savings in cost are
not likely to be significant.
The mattress should be anchored on the slope with screw anchors, driven anchors, or
buried anchors. If little toe scour is expected, and the outer edge of the mattress is not placed
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