Runup Characteristic: Vertical.
A post supported bulkhead consists of regularly spaced posts, usually timber, driven into the
ground with an attached facing material that forms a retaining wall. The posts support the bulkhead and
resist the earth pressures exerted against the structure. As with sheet piling, a post supported bulkhead
can be either a cantilever or anchored.
Their advantage is that once posts are emplaced, the facing material can generally be installed by
the landowner. Their disadvantage is that heavy equipment and trained personnel are often required to
install posts. The cost of the bulkhead depends on the spacing of posts and type of soil.
Hogwire Fencing and Stacked Bags
Hogwire fencing attached to posts can be used to support sand bags stacked on the landward side
of the fence (Figure A-7). The structure can fail for a combination of reasons, primarily the vulnerability
of the sand bags to tearing, which occurs when toe scour undercuts the structure and the bags slide
against the hogwire fence. However, the structure is relatively inexpensive. For best performance, use a
small mesh wire with PVC coating for longer life and protection of the bags. Provide toe protection or
place the bottom bags and fencing in a trench excavated to at least the depth of anticipated toe scour and
use only bags that are resistant to ultraviolet light. Tearing of the front row of bags can be prevented by
filling them with a sand-cement mixture. Burlap bags can be substituted for the more expensive bags
when a sand-cement mixture is used.
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