A solution for radial expansion of cylindrical cavities in sandy soils is presented. This solution is based on a rigid–plastic model that is not perfectly plastic and is valid even for large deformations (finite strains). Its application to the pressuremeter test is made by using the principle of similitude between cylindrical cavities together with a numerical–graphical technique for solving Palmer's equation, already published by the author. Two examples are presented. The computations are made by the ANABELA II program. It is found that this solution makes it possible to obtain the curve of the friction angles mobilized at each step of the test deformation. The importance of knowing the volumetric deformations associated with the shear is demonstrated as well as the differences in the curves of the angles of friction that are mobilized when finite or infinitesimal strains are used. Finally, the value of the friction angle mobilized at the critical voids ratio is discussed. An attempt is made to compute its value using the theory presented. Key words: radial expansion, cylindrical cavities, sandy soils, rigid-plastic model, not perfectly plastic model, finite strains, infinitesimal strains, mobilized friction angles, volumetric deformations, friction angle mobilized at critical voids ratio.
An invariant-based elasto-visco-plastic model for unidirectional polymer composites at finite strains