Effect of Void Ratio on K ₀ of a Sand by Means of Triaxial Stress-Path Testing

This paper presents an experimental technique using a computer controlled triaxial test to evaluate K₀, not requiring the use of any radial measurement transducers. It uses commercial software that applies a ramp of radial stress with back volume measurement and control. The method is applicable only to saturated specimens in drained conditions. The equipment used is briefly described, as well as the testing procedures. Results of laboratory tests on Toyoura sand specimens, with four different initial void ratios, are presented. For the preparation of all specimens tested, a dry funnel deposition method with undercompaction was used. It was concluded that, for the initial void ratios tested and for the stress level induced, stress-strain behavior fell in a narrow range the K0NC values were slightly higher for looser specimens, although lower than predicted by Jaky’s equation.