Geotechnical Analysis of Pile-Supported Embankments on Soft Soils

Construction on soft soils often results in significant settlement and other structural failures. In the case of very soft soils that are unsuitable for direct construction, a piled embankment provides a stable and reliable platform. When designing the piled embankment, there are two relevant factors, both related to the geosynthetic material of the geogrid, which include its stiffness and placement at the base of the embankment. In the present study, the embankment is constructed over soft soils such as peat, clay, and sand. Geosynthetic reinforcement, specifically geogrids, is used to enhance embankment performance. This piled embankment is the best solution that reduces large settlement and economically constructs the geosynthetic materials that are used as reinforcement to increase platform stability. A finite element analysis, PLAXIS 2D, is performed to calculate the tensile force acting on the geogrid and resulting settlements at a range of stiffness from 300 kN/m to 30000 kN/m. It is seen that as the geogrid's stiffness increases, the tensile force increases and therefore causes settlement to decrease. Finally, Terzaghi’s trapdoor test is used to develop theoretical formulae for calculating stresses induced by the arching effect in embankments.