Performance of Tape-Bonded Seams of EPDM Membranes: The Effect of Load on Peel-Creep.
Performance of Tape-Bonded Seams of EPDM Membranes: The
Effect of Load on Peel-Creep.
Rossiter, W. J., Jr.; Vangel, M. G.; Kraft, K. M.;
Embree, E. J.
Challenges of the 21st Century. Roofing Technology,
Fourth (4th) International Symposium. Proceedings.
First (1st) Edition. U.S. National Institute of
Standards and Technology, U.S. National Roofing
Contractors Association, Canadian Roofing Contractors
Association, National Research Council of Canada,
International Waterproofing Association, CIB, RILEM.
September 17-19, 1997, Gaithersburg, MD, 1-13 pp, 1997.
roofs; adhesive tapes; adhesive testing; bonding; creep
rupture; EPDM roofing membranes; microscopy; seams; time
A study was conducted to compare the peel creep-rupture
response (i.e., time-to-failure or TTF) of tape-bonded
and liquid-adhesive-bonded seams of EPDM
(ethylene-propylene-diene terpolymer) roof membranes.
Two commercial tape systems (i.e., tape and primer) and
one liquid adhesive were applied to well-cleaned EPDM
rubber in the NIST laboratories. The creep-rupture
experiments were conducted at 23 deg C (73 deg F) and 40
percent to 45 percent relative humidity under peel loads
ranging from 3.1 N to 24.9 N (0.7 lbf to 5.6 lfb). For
each adhesive system, the data were found to be fitted
well by the model. The conclusion was that the
tape-bonded sample sets had mean times-to-failure that
were, in most cases, comparable to or greater than those
of the liquid-adhesive-bonded sample sets. In addition,
the tape-bonded specimens provided time-to-failure
results that were reproducible between replicate sets.
In a related experiment, the creep-rupture response of
six sets of tape-bonded specimens prepared in the
laboratories of EPDM membrane manufacturers was compared
with that of NIST-prepared tape-bonded sample sets.
Five of six manufacturer-prepared samples sets had
similar, or longer, times-to-failure than the
NIST-prepared sample sets at low creep loads. In the
case where the manufacturer-prepared sample sets had a
statistically significant shorter time-to-failure than
the NIST-prepared sample sets, the difference was not