Abstract
During a self-boring pressuremeter test (SBPMT), a cylindrical cavity is expanded from finite radius. With this view, a method for estimating volumetric strains in expanding plastic zone based on finite strain analysis is developed to solve the problems related to expansion of cylindrical cavity from a finite radius in sands. Using finite strains, average value of volumetric strains in the plastic zone is calculated at various values of circumferential strains (εθθ) ranging up to about 30%, when the value of angle friction (φ) is varying between 25 and 45 degrees and the value of rigidity index (Ir) is varying between 5 and 1000. The dimensional cavity expansion factor (F"q) is calculated using cavity expansion theory to develop F"q versus εθθ curves at various values of φ and Ir. In the companion paper, Gupta (2005), this method has been applied to analyze the SBPM tests performed in sands for determining φ, Ir, and modulus of deformation (E) at different stress levels.
