B. The Installation Contractor is responsible for providing and operating an on-
site tensiometer and corresponding sample cutting equipment to perform all
trial and field seam testing.
C. Trial seams shall be produced under the same physical conditions as
production seaming.
D. Trial seam sample testing:
1. Trial seams shall be a minimum of 5 feet long and 12 inches wide
(perpendicular to the seam).
2. One-inch wide samples shall be cut perpendicular to the seam and tested
according to ASTM D6392 in a tensiometer for bonded seam strength
(shear) and peel adhesion.
3. Two (2) samples will be tested for shear and five (5) samples for peel (10
peel tests total for fusion welds as both edges of the weld must be tested).
Two passing shear tests and 4 out of 5 passing peel tests (9 out of 10 for
fusion welds) are required for an acceptable trial seam.
4. Each sample failure must consist of a ductile break that is film tearing
bond and must meet the strength requirements of the following table:
Peel Adhesion Extrusion ASTM D6392 78 lb/in
E. Ifa trial seam test fails, then another trial seam shall be performed and tested.
If the second trial seam fails, then the seam welder shall not be used until it is
repaired or faulty conditions are corrected, and two trial seams pass the
destructive tests.
F. Arecord of the date, time, ambient weather conditions, test results, operator,
and equipment number shall be kept by the Installation Contractor, and
submitted to the CQA Consultant on a weekly basis. A properly identified
unused section of the trial weld seam will be retained by the OWNER.
3.6 INSTALLATION CONTRACTOR QC TESTING
A. The Installation Contractor shall non-destructively test the full length of all
seams to ensure watertight, homogeneous seams. Test methods shall consist
of vacuum box testing, air-pressure testing of double-fusion seams, or other
methods approved by the manufacturer and the CQA Consultant. The test shall
be performed as work progresses, rather than at the completion of all field
seaming.
B. Vacuum box testing shall be performed on extrusion welds using a vacuum box
with a rigid housing, transparent viewing window, a soft rubber gasket on the
bottom edge, and a valve assembly with a vacuum gauge. The vacuum box
File No. 3066.09.00 Geomembrane 02550 - 11 of 14 December 2017
