Secondary anchors were designed as a supplement to the existing anchors. They consist of a 1 inch diameter coal tar epoxy coated steel rods, 12' long, but preferably 16' (where possible), encased in PVC and anchored with a reinforced concrete deadman. (Approx. 48" wide x 18" high x 12" thick).
Structurally head1 the portion of the seawall that is anchored.
Supports only that portion of the wall anchored leaving the seawall prone to failure in other areas.
Should be used primarily when a seawall only needs upper support.
If not re-coated periodically (which is seldom done) has life span of approximately 10 years.
Should be only installed when only upper support is required. Anchors do little to stop a mid point or mud line failure.
Anchor blocks should be installed as deep as possible. (In most cases 3'-6" to 4'-6" to the bottom of the block is a good rule of thumb.)
Anchor blocks should be installed landward of the seawall as far back as possible preferably 16' and if necessary cutting a pool deck to achieve this distance is not out of the question.