When sheet that was laid warm cools and shrinks, it lifts off the subgrade wherever the ground changes direction, bridging the toe or a corner. If cover soil is placed on it in that state, the sheet is strained and can tear or crack, and the gap breaks contact with the GCL or clay below. Leaving enough slack and covering while the sheet is relaxed prevents it.
Liner is trampolining across the toe this morning, so don't push dirt on it until it relaxes in the sun.
Also heard as
- bridging
- bridged liner
Related terms
Waves
Installer word for the wrinkles that form in a geomembrane as it expands in the sun.
Anchor trench
Trench along the top of a slope where the edge of a geosynthetic is buried to hold it in place.
Composite liner
Barrier made of a geomembrane in direct contact with a low-permeability soil or GCL layer beneath it.
HDPE
High-density polyethylene: the stiff, chemically resistant polymer used for most landfill and mining geomembranes.