Isotropic yield surfaces in three dimensions for use in soil mechanics

Abstract

Abstract When using numerical methods in soil mechanics, one often needs to define a yield surface in three‐dimensional principal‐stress space. A special class of yield surfaces, given by J = ( p + a )α(1−β sin 3ν) n , where ν is the Lode angle, is considered from the point of view of convexity and agreement with experimental data. Some recently proposed yield functions which belong to this class are compared. It is shown that the model with n = −0.229 is optimal as regards convexity, and can give reasonable agreement with the data.