A look at 3 reasons for clean stone backfill behind a segmental retaining wall construction.
1- Ease of compaction
The level of compaction is already at 95%, right when it’s dumped out of the truck.
It does not require a lot of effort to get it to 100% of its density.
Since we need less effort of compaction, the risk of pushing the wall forward is minimal as well.
2- Filtration qualities
We recommend a 3-feet column of clean stone behind the wall.
The ground or surface water brings sediment. The water, along with its sediment, will travel through the back cut and float down the drain tile we installed.
Using clean stone allows the settlement to bypass our drain. The water will float in the pipe and evacuate.
To know more about drain tile installation, refer to this article : http://pros.techo-bloc.com/drain-tile
3- Drainage characteristics
The main purpose of clean stone is not primarily a drainage medium.
Drainage is usually its last-ditch effort.
The area and the toe of the wall still need to be capped with an impermeable liner of clay in order to stay dry.