Because fibers outside the jaws share the load, the grab result runs higher than a full-width test and reflects resistance to concentrated pulls during placement. It is reported as a force in pounds or newtons, not force per width, which makes it handy for specs and quality control but useless for reinforcement design. North American specs and survivability classes lean on it heavily.
Conformance sample broke at 180 pounds grab tensile against a 200 MARV, so that lot is on hold.
Also heard as
- grab strength
- grab
- grab test
Do not mix it up with
- Wide-width tensile: Wide-width tests a 200 mm specimen gripped across its full width and gives strength per unit width for design.
Related terms
Wide-width tensile
Tensile test across a 200 mm wide specimen that gives strength per unit width for reinforcement design.
MARV
Minimum average roll value: the lowest average test result a product guarantees for any roll it ships.
Survivability
A geosynthetic's ability to make it through shipping, placement and compaction without being damaged.
AASHTO M 288
US highway specification for geotextiles that sets required properties by application and survivability class.