Embankments reinforced by piles and geosynthetics-Numerical and experimental studies dealing with the transfer of load on the soil embankment

摘要

The dimensioning of geotechnical earth structures is, due to the use of new technologies and new materials, more and more sophisticated. It is particularly the case for the embankments reinforced by piles and geosynthetics. Two main mechanisms are governing the behaviour of this kind of structures: an arching effect (or transfer of load) into the soil embankment and the membrane effect of the geosynthetics sheet. Thus, the vertical load of the embankment can be directly transferred to the piles by an arching effect or indirectly via the membrane effect of the geotextile. A great part of the load of the embankment is by this way supported by the piles. To improve the understanding of the behaviour of embankments on piles reinforced by geosynthetic sheet, a numerical study dealing with the transfer of load into the soil embankment was initiated. It is based on the used of a coupling between finite and discrete element methods especially developed to model this kind of structures. One part of the numerical analyse consists to a parametrical study testing the influence of the size of the piles cap, the geosynthetics stiffness, the height of the embankment and the rigidity of the underlying soil. The other part deals with the comparison between the numerical model with experimental results of a true scale experiment. A particular attention is paid to show the load transfer mechanisms and the membrane effect.