Stress characteristics for bearing capacity in sand using a critical state model

Abstract

A new stress characteristic solution has been developed for two-dimensional strip footings on the surface of a sand layer. The analysis uses sand properties defined by a critical state model. This analysis takes account of different stress levels, different placement densities, the sand compressibility, and the transition from strain softening to strain hardening behavior that accompanies increased stresses. The results show linear relationships between log (Nγ) and log (footing breadth) that depend on the details of the sand model used. The results have been compared with available summaries of laboratory- and field-scale results. Although the critical state models for the sands used in the experimental studies cannot be fully developed from published information, nevertheless the trend of the results is encouraging. Additional information on validations of the critical state sand model is needed. Key words: surface footings, stability, capacity coefficients, self-weight, plasticity, stress characteristics, critical state.