Settlement patterns of soft soil foundations under embankments

The settlement pattern of an embankment may not always be the typical one in which the maximum settlement occurs at the center. Other patterns may develop with changes of embankment width or surcharge arrangements, which will require special settlement calculation methods and engineering measures. This paper compares the characteristics of shear stress distributions and effective stress paths in foundations induced by several embankment loads. Based on the analyses, the patterns of foundation settlement are classified into four categories, i.e., one-dimensional, sagged, transitional, and typical basin types. A simplified procedure is presented to identify settlement patterns based on shear stress analyses, and a case study is reported to illustrate the procedure. Embankment width, embankment height, and foundation soil conditions are found to be most critical to settlement patterns. However, this paper does not purport to provide methods of estimating the magnitude of settlement.