Enhancement of bearing capacity from consolidation: due to changing strength or failure mechanism?

Abstract

Bearing capacity of shallow foundations is higher following preload (or self-weight)-induced consolidation because the soil strength changes, and perhaps because the failure mechanism changes. Previous studies have illustrated this effect by plotting or predicting changes in either bearing capacity factor or strength. This study explores the relative contribution of these two effects. This is achieved by formalising a definition of bearing capacity factor, which is described in terms of the average strength mobilised in the deformation mechanism at failure. Using the alternative definition of bearing capacity factor, the gain in foundation capacity is shown to be almost entirely due to changes in soil strength, rather than bearing capacity factor, which remains largely unaffected by the strength gains. This observation should encourage future studies into consolidated bearing capacity to present gains in capacity in terms of changes in mobilised strength rather than changes in bearing capacity factors, and supports the use of prediction methods that focus on defining the change in soil strength.

Improvements in plate anchor capacity due to cyclic and maintained loads combined with consolidation

“…Changes in foundation capacity can be interpreted solely as changes in soil strength, because any changes in the failure mechanism caused by the changing soil strength have minimal influence on the bearing factor Nc,a (Stanier & White 2019). The framework, therefore, focuses solely in the variation in su, in order to predict changes in qa.…”

Generalized predictive framework for lateral break-out resistance of submarine pipelines considering nonlinear seabed geometry and consolidation

“…The improvement in maximum consolidated resistance is linked with the enhancement of soil strength due to consolidation (e.g. Chatterjee et al, 2014, Feng and Gourvenec, 2015, Stanier and White, 2019 as per the following equation:…”