A comparative study of a new subgrade model on beams with respect to FE and existing analytical models

ABSTRACT A variety of mechanical and continuum subgrade models ranging from the simplest Winkler model to the more complex ones were proposed in the past to address the problem of foundations on elastic subgrades. Most of them are based on simplifying assumptions. With the objective of arriving at a reliable few-parameter analytical model, two- and single-parameter mechanical equivalents of a rigorous continuum foundation model proposed by the first author are presented that are adjusted with respect to the finite-element (FE) software, PLAXIS. The performance of both variants of the model is tested on beams by comparing with other analytical models and with FE models for a range of variables. Both variants performed remarkably well, especially the two-parameter variant. The adjusted model parameters are provided for practical use. Adjustment factors are also established for the popular Vlasov’s model. Comparison between the proposed and FE models shows that Vlasov’s adjustment factor is sensitive and varies over a comparatively wide range, and the model even becomes unadjustable for short beams. In contrast, the proposed models consistently yield very good results for all ranges of beams with an adjustment factor that is less sensitive and varying within a narrow range confirming their good quality.