Evaluating the Bearing Capacity of a Soil Layer Overlying Rigid Substratum Using a Modified Failure Mechanism Based on Limit State Analysis

Abstract:

The bearing capacity of shallow foundations resting on a soil layer with a finite depth over bedrock has been studied for years by many investigators. Farzaneh et al (2010) introduced a rigorous bearing capacity analysis based on the upper bound state theorem, using a log-spiral surface algorithm. This paper presents a thorough evaluation of this collapse mechanism and subsequently, a modified failure mechanism is introduced. The collapse mechanism consists of rigid blocks under combined rotational and transitional movements. The effects of the loading parameters on bearing capacity results are then discussed. The findings of this study are compared with the original limit state mechanism as well as previously published solutions, emphasising the accuracy and efficiency of the modified mechanisms. Furthermore, parametric studies are carried out to evaluate the ultimate bearing capacity of shallow foundations resting on a restricted soil, layer using the proposed mechanism. Design tables are finally presented for practical use in geotechnical engineering.

• Periodical: Applied Mechanics and Materials (Volumes 353-356)
• Pages: 806-814
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.353-356.806
• Online since: August 2013
• Authors: Reza Afshar-Mazandaran, Hadi Khabbaz
• Keywords: Bearing Capacity, Rotation-Translation Collapse Mechanism, Upper-Bound Limit State Analysis

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