Numerical simulation of the compaction effect and the dynamic response of an oscillation roller based on a hypoplastic soil model. Issue 132 (May 2020) - Paulmichl, Ivan
Abstract: This paper presents a numerical model that facilitates for the first time the numerical prediction of both the dynamic response acceleration and the compaction effect of an oscillation roller during near-surface compaction of non-cohesive, granular and dry (or earth-moist) soils. In this plane-strain model, the intergranular strain enhanced hypoplastic constitutive model captures the nonlinear inelastic behavior of the soil below the drum. A "protective foil" is applied to the soil surface to ensure the numerical stability of the model solved with the Finite Element software suite ABAQUS/Standard. The roller model includes the drum, the suspension between the drum and the roller frame, and the static and dynamic forces applied to the drum. Dry friction according to Coulomb's law describes the contact between the drum and the soil surface. As such, the stick-slip motion of the drum can be simulated. The derived stresses, strains, the change of the void ratio in the subsoil representative for the compaction effect, and the dynamic response of the drum center are analyzed in detail. In addition, the soil response is compared with the outcomes of a static roller pass. It is shown that the developed model qualitatively predicts the fundamental response characteristics of the interacting oscillation-subsoil system observed in field tests.