Abstract
Embankments reinforced with piles and geosynthetic is one of the improvement techniques that provides a good solution for rapid construction of highways and roads over poor grounds (e.g., soft clay, peat, loose sand, etc.). In this paper, a case history of highway project, which was constructed rapidly on weak soil deposits in Alexandria, Egypt, is presented. Moreover, because of the complexity of the problem of soil-structure interaction associated with reinforced pile embankment, finite element method (FEM) PLAXIS 2D subroutine was utilized to simulate the problem and to investigate the response of the embankment during construction, operation, and seismic event. The numerical modeling results revealed that, the proposed system of piled-embankment reinforced with geosynthetic founded on a soft clay has a substantial impact on reducing both of vertical settlements and construction time significantly. The numerical model predicted a reduction in total vertical settlement from 250 mm to 90 mm (i.e., 64% reduction percentage) compared to the calculated values of the unreinforced embankment numerical model. Furthermore, the proposed treatment method gave acceptable stability results in terms of safety factors for static (FOS=3.9) and seismic (FOS=2) states compared to the unreinforced embankment which failed to give the minimum required safety factors by design standards and regulations.