Installation Instructions

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RETAINING WALLS
Step 1 - Preparation for Grid
The area behind the wall on the grid layer
needs to be level with the top of the block
(after compaction) and compacted to 95% of
the Standard Proctor density (ASTM D698).
BASIC GEOGRID REINFORCEMENT
Step 2 - Grid Placement
Place the grid as close to the face of the wall
without exposing it after successive placement
of blocks. Ensure the grid is placed with the
strength direction perpendicular to the wall.
Remember, bidirectional grids (2xT) are the
same strength in both directions and can be
rolled out parallel on straight walls. Check grid
manufacturer specications for proper grid
placement instructions. (3xT is undirectional).
Step 3 - Preparation for Backfill
Place the next course of block. Pull the grid
back and stake it so it is taut and free of
wrinkles.
Step 4 - Backfill and Compact
Place 3/4" to 1" clean aggregate (crushed
rock) within the cores and a minimum of 12"
behind the blocks. Also, place and compact
backll on the grid in lifts no greater than 3 to
6 inches at a time depending on the rating of
your compaction equipment. When possible, it
is recommended that the backll be deposited
directly behind the wall and pushed to the end
of the grid to ensure that it remains taut and
wrinkle-free.
Step 5 – Install Additional Courses
Repeat steps 2, 3 & 4 to complete wall to
height required, installing additional layers of
grid where needed.