Assessing the Nonlinear Load-Deformation Relationships of Vertically Loaded Shallow Foundations on Clays using the Seismic Piezocone Testing

Abstract

Assessing the load-deformation behavior is an essential aspect in geotechnical designs of shallow foundations. Reasonably accurate estimates of the settlement of foundations under different loading conditions are crucial for highly compressible clays. Nevertheless, current design procedures, utilizing linear elasticity, cannot accurately predict soil deformations under loads as the stress-strain of soils is highly nonlinear, even under small loads. Thus, it is not uncommon to have significant differences between observed and estimated settlement values. In the presented study, a new procedure is proposed to estimate shallow foundations' nonlinear behavior resting on intact non-fissured clays using in-situ seismic piezocone (SCPTu) testing. The parameters of the nonlinear behavior are assessed using the results of the SCPTu. Followingly, load-deformation of shallow foundations is determined. Well-documented case studies are backanalyzed to validate the procedure. A close agreement is shown between the predicted and observed load-deformation relationships, implying that the approach can be utilized for similar cases.