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Measuring the parameters that control the deformability and strength of soils through either laboratory experiments or in situ testing is critical for numerous applications in geotechnical engineering. While image- and wave-based techniques are increasingly prevalent, there is a perpetual need for techniques capable of sensing local, nonlinear properties, for which mechanical testing is the only viable option. Existing methods for inferring mechanical properties have evolved largely by trial and error, and there is no general, systematic approach for evaluating one possible approach against another. As a first step toward addressing these challenges, this paper describes a quantitative metric that can discriminate between different types of mechanical tests with respect to how well they are able to recover the true mechanical properties of the material. The metric is devised by (1) creating a min-max optimization of parameter sensitivities, considering the local and global topological properties of the forward model, and (2) evaluating the metric for fundamental material tests. 

This work focuses on the numerical simulation of multi-plate anchor systems (e.g., helical anchors) in sand subjected to vertical loading. In assessing the stiffness and capacity of these multi-plate anchor systems, full awareness of the abilities and limitations of the various analysis methods must be understood. This work first summarizes studies completed by others and then goes on to assess the failure mechanisms of multi-plate anchors in sand and the influence of (1) plate width-to-depth ratio, (2) number of plates, and (3) relative positioning of plates. The analysis makes use of (1) conventional limit analysis, (2) so-called modified limit analysis that employs reduced strength parameters to account for the influence of soil dilatancy, and (3) the displacement-based finite element method, which considers elastic as well as plastic deformation leading to failure. The work critically reflects on limitations in the current analysis methods for helical ground anchors.