Viscoelastic Parameter Prediction of Multi-Layered Coarse-Grained Soil with Consideration of Interface-Layer Effect

Abstract

Study on viscoelastic properties of the multi-layered coarse-grained soil (CGS) is very important for safety assessment and disaster prevention of subgrade engineering. Current research work is mainly focused on the one-layered CGS and the actual pebble inclusion of irregular polyhedron is usually simplified as an ideal shape of sphere or ellipsoid. Very few studies are available for predicting viscoelastic parameters of the multi-layered CGS. In this paper, a new method is proposed to predict viscoelastic parameters of multi-layered CGS based on the homogenization method and elastic–viscoelastic corresponding principle, in which the interface-layer viscoelasticity and the actual shape of pebble inclusion are firstly taken into account. Research results show the creep deformation is decreased with the increase of the shape factor (ρ) of pebble inclusion, and the interface-layer height (h) and numbers (N). ρ is in the range of 1–1.8 and the suitable interface-layer height is 20–30% as much as the height of one-layered CGS. The tested creep curves of the multi-layered CGS agree well with the predicted ones and can prove the existence of the interface-layer (considering at least one interface-layer) and verify the validity of this new interface-layer method.