Resistance of Geosynthetics to Liquids for
additional guidance on compatibility testing.
Geotextiles may also be used to provide puncture
protection for geomembranes. Needle-punched
nonwoven geotextiles are commonly used to provide
puncture protection. GRI Report Number 13 - A
Design Methodology for the Puncture Protection of
Geomembranes provides guidance on the design of
geotextile cushion layers. Typical index properties
for a 350 g/square meter geotextile are shown below:
MINIMUM REQUIREMENTS FOR PROTECTION GEOTEXTILE
------------------------------------------------------
PROPERTY
UNITS ACCEPTABLE VALUES TEST METHOD
------------------------------------------------------
GRAB STRENGTH N
1420
ASTM D 4632
------------------------------------------------------
PUNCTURE
N
930
ASTM D 4833
------------------------------------------------------
TRAP TEAR
N
555
ASTM D 4533
------------------------------------------------------
MASS/
G/SQ M
350
ASTM D 4751
UNIT AREA
------------------------------------------------------
UV
PERCENT
50 AT 500 HRS ASTM D 4355
DEGRADATION
------------------------------------------------------
Apparent opening size and permittivity are not
critical properties when specifying geotextiles used
for puncture protection. Seams for protection
geotextiles are generally overlapped a minimum of
305 mm (12 inches). Sewn seams are generally not
used for puncture protection geotextiles.
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Geotextile shall be a [woven] [nonwoven] pervious sheet of polymeric
material and shall consist of long-chain synthetic polymers composed of at
least 95 percent by weight polyolefins, polyesters, or polyamides. The use
of woven slit film geotextiles (i.e. geotextiles made from yarns of a flat,
tape-like character) will not be allowed. Stabilizers and/or inhibitors
shall be added to the base polymer, as needed, to make the filaments
resistant to deterioration by ultraviolet light, oxidation, and heat
exposure. Regrind material, which consists of edge trimmings and other
scraps that have never reached the consumer, may be used to produce the
geotextile. Post-consumer recycled material [may also] [shall not] be
used. Geotextile shall be formed into a network such that the filaments or
yarns retain dimensional stability relative to each other, including the
edges. Geotextiles shall meet the requirements specified in Table 1.
Where applicable, Table 1 property values represent minimum average roll
values (MARV) in the weakest principal direction. Values for AOS represent
maximum average roll values.
SECTION 02373
Page 8
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