Numerical modeling of reinforced unpaved roads by geogrid

Abstract

In this paper, numerical computations using Flac software are carried out to investigate the improvement of the bearing capacity of a reinforced unpaved roadway over soft clay. Placed between the subgrade and base course, or within the base course, the geosynthetic improves the performance of unpaved roads carrying channelized traffic and unpaved areas subjected to random traffic. The present study focuses on the mechanisms by which the reinforcement improves the behavior of the roadway under the effect of a static single load. The loading of the road is carried out by imposed displacement of the load contact until reaching a final displacement called rut. The pressure-displacement behavior was determined for small and large strain analysis for unpaved roads with or without reinforcement. The analysis of the distribution and the importance of tangential and normal stresses on the soil-base interface provide an explanation to the effect of the reinforcement in the improvement of the bearing capacity or what is commonly called mechanism of reinforcement. The study also highlights the effect of the stiffness and the anchorage length of the geogrid on the reinforcement

Keywords

• Modeling, unpaved road, reinforcement, large strain, geogrid

References

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