Updated normalized load-settlement model for full-scale footings on granular soils

Abstract

The design of spread footings on granular soils is generally governed by serviceability requirements. Recent studies have utilized databases of load tests to investigate the use of normalized load-settlement curves to model the behavior of footings on sands. A major limitation of available databases is that they are based primarily on data from plate load tests or footings that have an equivalent width smaller than 1.0 m. There is a need to confirm the applicability of these curves to footings of practical scale. The main objective of this paper is to update available normalized load-settlement curves using point measurements of settlement and load from full-scale footings. Bayesian techniques are employed in the updating process. Results indicate that the updated normalized load-settlement relationship is slightly more conservative but less uncertain than the current relationship. Results from an illustrative example involving serviceability limit state reliability analyses using footings with widths ranging from 1.5 to 3.0 m indicated that the updated relationship resulted in a slightly higher reliability level compared to the prior relationship.