Chapter 5 Analysis of subsoil deformations

Abstract

This chapter discusses the analysis of subsoil deformations. The design of embankments on organic soils involves estimation of the magnitude and rate of the subsoil deformations. A study of deformations in organic soils under embankments demonstrates large vertical and horizontal displacements in the loaded zone of the subsoil. Observations of the deformation development show that the greater part of the horizontal displacements appear during loading and shortly afterward. These results indicate that, except for the early phases of construction, the horizontal movements do not play any significant role in the consolidation process. Therefore, the calculation of settlement and excess pore pressure dissipation with time can be performed with one-dimensional analysis taking into account initial elastic deformations. Due to the significant variability of the soil parameters during a consolidation process and the large vertical displacements in the subsoil, the consolidation prediction should be based on a method which can account for the non-linear soil characteristics, the large deformations in the subsoil and preferably also the creep effects.