Geotextiles used as reinforcing - LMS - EPFL

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MD / December 1997. Geotextiles used as reinforcing. Soil Mechanics Laboratory (LMS). GCB (Ecublens) CH- 1015 LAUSANNE. ¤: 021 - 693 23 15 TÉLÉFAX: ...
Soil Mechanics Laboratory (LMS) GCB (Ecublens) CH- 1015 LAUSANNE : 021 - 693 23 15 TÉLÉFAX: 021 - 693 41 53 http://lmswww.epfl.ch/lms_f.html; e-mail: [email protected]



Geotextiles used as reinforcing Over the last few years, the use of getextiles has shown itself to be one of the most popular techniques for the improvement of soils and earth structures. Four roles, which may also be combined, are attributed to geotextiles: drainage, filtration, separation of layers with different grain size distributions and mechanical reinforcement. This last aspect, which has been used after the other three, is now the source of a steadily increasing number of promising applications. The deformability and high strength of layers of geotextiles are, in effect, particularly well adapted to the mechanical properties of soil deposits. The design methods for structures reinforced in this manner are far from perfect and a sizeable research effort remains to be carried out. It is this aspect that the LSM decided to work on for over six years. The research was initiated with tests on smallscale models using, in particular, the X-ray technique for the measurement of deformations inside the model. Then, large-scale tests on slopes reinforced with geotextiles were undertaken in the Òhalle fossesÓ test hall (Figure 1). These tests, carried out with layers of both woven and nonwoven geotextiles, permitted the precise observation of deformation mechanisms and

É C OL E PO L Y T EC H NI QUE FÉ DÉR AL E DE LA USANNE

failure of the reinforced slopes under loading cycles simulating roadway traffic (Figure 2). The analysis of the results of these tests will permit the improvement of design methods and the execution of more economical reinforcements than those constructed at the present time. crack

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Figure 2: Deformations and failure mechanisms of a slope reinforced by layers of geotextiles

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Figure 1: The large-scale model of a slope reinforced by layers of geotextiles

Publications Kharchafi M., Dysli M. - Mechanical performances of two experimental full-scale embankments reinforced by geotextiles. 5th Int. Conf. on Geotextiles, Geomembranes and related Products, Singapore, Sept. 1994. Kharchafi M., Dysli M. - Untersuchungen Ÿber geotextil-verstŠrkte Bauwerke. K_GEO92, Luzern, Mai 1992. MD / December 1997