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Proceedings of the 18
th
International Conference on Soil Mechanics and Geotechnical Engineering, Paris 2013
For the HDPE geomembranes δ
max
was rather
insensitive to the variation of degree of saturation. The
mobilized tensile force in the geomembrane was also insensitive
to the variation of soil degree of saturation, with some higher
values for some tests, but without allowing a conclusion on the
influence of moisture content on the value obtained (probably a
result of test scatter).
The highest values of F were obtained in the tests with
the texturized HDPE geomembrane, whereas the lowest ones
were obtained in the tests with the smooth PVC geomembrane.
The smallest values of δ
max
were also obtained in the tests with
the smooth PVC geomembrane.
4 CONCLUSIONS
This paper presented results of ramp and direct shear
tests on different geomembrane products in contact with a sandy
soil. The degree of saturation of the soil was varied during the
test to assess possible influence of this parameter on the
adherence between soil and geomembrane. The results obtained
showed that the interface friction angle between soil and
geomembranes was insensitive to the variation of soil degree of
saturation for the conditions employed in the test programme.
A progressive interface failure mechanism was observed in the
tests with PVC geomembranes due to the more extensible
nature of this type of geomembrane.
The largest values of interface friction angles were
obtained in the tests with the texturized HDPE geomembrane,
whereas similar lower values were obtained in the tests with the
smooth PVC and HDPE geomembranes. As a consequence of
higher adherence with soil, the largest mobilized tensile forces
were obtained in the tests with the texturized HDPE
geomembrane.
5 ACKNOWLEDGEMENTS
Authors would like to thanks Maccaferri, Sansuy e
Nortene Geosynthetics Ltd. for having supplied the
geomembrane products tested. The authors are also indebted to
the University of Brasilia, CAPES-Brazilian Ministry of
Education and CNPq-National Council for Scientific and
Technological Development for the financial support.
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