Reliability Analysis for Settlement of Shallow Bridge Foundations: Fid-Bau Portal

Reliability Analysis for Settlement of Shallow Bridge Foundations

Ahmed, Aseel Y. / Nowak, Andrzej S. / Szerszen, Maria M.

Stability is one of the most important problems of soil mechanics related to the condition of excessive settlements. A reliability-based approach can be applied for designing shallow foundations for which their design needs knowledge about the distribution of settlement under a given footing is considered. The performance of geotechnical structures, including shallow foundations depends mostly on loads and soil properties that are the random variables described by statistical parameters. The objective of this study is to develop the methodology for risk analysis procedures of shallow foundations. This required the development of the reliability models that can be applied to shallow foundations and involved the establishment of serviceability limit state functions. Reliability is expressed in terms of reliability indices, which are calculated for total settlement of shallow bridge foundations. The most important part of this study is the development of statistical models for total settlements of shallow foundations on cohesionless soils by Monte Carlo simulations technique. The study verifies the most accurate settlement prediction methods for calculating immediate settlement of spread footings for each site by using compiled field data from research projects based on vertical settlements measured on 23 sites of footings for ten bridges in Northeast U.S. and two bridges in Ohio. Reliability indices are determined for settlement of the spread footings assigned in this study. CE Database subject headings: Reliability analysis; Shallow foundations; Immediate settlement; Cohesionless soils; Settlement prediction methods; Statistical parameters; Reliability index.