Triaxial tests in geogrid reinforced soil
DOI:
https://doi.org/10.14195/2184-8394_118_3Keywords:
Reinforced soil, Geogrids, Triaxial testsAbstract
This paper presents a discussion on the results of a series of triaxial tests on geogrid reinforced soil. These tests were carried out on specimens of a sandy soil and a clayey silt, reinforced with 1, 2 and 4 geogrid inclusions, under several confining levels. This investigation aimed at evaluating the changes in strength and stiffness with the introduction of horizontal reinforcing layers. Due to the geometric charac teristics of the geogrid, all tests were made in a large triaxial device at the geotechnical laboratory of Cedex, in Spain. The results indicated an increase in strength and in stiffness when the number of geogrid layers increases. It was also noted that the volumetric compression of the reinforced soil also increased with the number of geogrid layers. This suggests that the inclusion of reinforcement elements in a soil mass causes an effect similar to an increase in effective confinement. In addition, the paper presents a discussion on the different loading modes of the reinforcement layers during the triaxial tests. These loadings induce an effect similar to an increase in confining stress, which results in an increase in strength of the reinforced soil.
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