Empirical Models to Formulate the Nonlinear Response of Rocking Shallow Foundations

Abstract

This paper aims to introduce a simplified moment-rotation backbone model for exploring the nonlinear behavior of shallow foundations subjected to rocking. The model is developed based on parametric numerical investigations of rectangular footings on dense dry sand, taking advantage of a nonlinear macro-element model verified based on a set of experimental results. Empirical expressions are proposed for rocking stiffness degradation due to gravity loads and foundation rotation as a function of the factor of safety against vertical loads and aspect ratio of foundations. Similar to previous researches, the uplift reference rotation was introduced to explore a new closedform expression appropriate for normalizing the foundation response in a non-dimensional form. The proposed approach for stiffness degradation and nonlinear backbone model of rocking foundations aims to be simple, to minimize the dependence on the variable parameters, and to provide physically sound selections for engineering applications.

Predictive modeling of rocking-induced settlement in shallow foundations using ensemble machine learning and neural networks

“…Empirical relationships have been proposed for the estimation of permanent settlement of rocking shallow foundations using either the static vertical factor of safety (FS v ) or critical contact area ratio (A/A c ) of foundation and the cumulative rotation experienced by the foundation during earthquake loading Hamidpour et al, 2022). A/A c is conceptually a factor of safety for rocking foundations taking into account the change of contact area of the footing with the soil during rocking (Gajan and Kutter, 2008).…”