The Longard tube depends on its weight to resist overturning and on friction to maintain its
position. It is designed to protect the toe of the bank from wave attack, and not necessarily to resist earth
pressures. The tube should not be placed directly against the base of a bank or overtopping waves may
continue to cause erosion. It should be placed far enough from the toe so that overtopping waves will
form a sand berm between the tube and the bank. Wave energy will be absorbed by this berm, and
further bank erosion may be prevented. Placement of other devices or another tube on top, to increase
the structure height and prevent overtopping, is not recommended.
Stacked Used Tires
Wave Height Range: Below two feet.
Because used tires are readily available at most sites at no cost, many have tried to use them for
shoreline protection devices. The bulkhead on Figure 40 was made with scrap tires interconnected (both
vertically and horizontally) by galvanized spikes and pushnuts. The tires were stacked in a staggered
pattern over a filter cloth, and granular material was used both as backfill in low areas, and as fill in the
tires. Three rows of galvanized steel anchors secured the structure to the beach. The structure
progressively failed because the interconnections between the tires were inadequate to hold it together.
The gravel washed out of the tires, eventually allowing them to be lifted by waves. This system is not
recommended in view of better and less costly alternatives.
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