Numerical investigation of the at-rest earth pressure coefficient of granular materials

Abstract

The at-rest earth pressure coefficient, K 0 , is one of the most fundamental values for evaluating in-situ soil stresses and designing foundation. Research has been expanded to investigate the correlation between K 0 and micro-scale characteristic of granular soils, beyond the macroscopic approach empirically correlated with internal friction angle. This study presents the evolution of K 0 values of irregularly shaped natural sand, spherical shaped smooth and rough surfaced glass beads along with the stress history, estimated by the discrete element method. The surface roughness and non-spherical particles were emulated by inter-particle friction coefficient and the clumped particles. Results exhibit that the K 0 during loading stage nonlinearly decreases with increasing values of friction coefficient and the assemblies with clumped particles present the lower values of K 0 than spherical particle assemblies of the same friction coefficient. The varying friction coefficient seems enough to capture the evolution of K 0 during loading, unloading and reloading cycles, while the natural sand inevitably B Junhwan Lee requires the assembly with clumped particles to capture the experimentally observed K 0 evolutions.

Measurement of the Lateral Earth Pressure Coefficient of Clayey Soils by Modified Oedometer Test

“…According to published research, other factors may also affect the K0 value, including, at a minimum, the soil type, degree of consolidation [6][7][8], the void ratio [9], state of stress [10], the saltiness of pore water [11] and the shape of particles [12].…”