Woven Geotextile Fabric
Separation is the primary geosynthetic function in systems with firm subgrades (CBR > 3). In weaker subgrades, reinforcement geosynthetics areused to stabilize the system particularly in wet, saturated conditions.  Separation is the prevention of subgrade soil migration into an aggregate base(or subbase), and prevention of the aggregate base (or subbase) migration into the subgrade.

Base Separation is of critical importance to the success of the Interlocking Concrete Pavement is the stabilization of the base material.  Woven geotextiles are recommended in most situations to preserve the load bearing capacity of the base over a greater length of time and provide filtration and drainage for permeable paver systems.

Filtration is restricting the movement of soil particles, while allowing water to move from the filtered soil to the adjacent coarser soil.

Filtration geotextiles also provide separation by preventing movement of the subsoil, but allowing water to pass throughout the system.  Woven geotextiles are recommended in permeable paver applications to provide both separation and filtration. Monofilament woven geotextiles provide long term filtration and separation allowing permeable pavers to drain storm water run-off.