Abstract
Fibre reinforced soils have been investigated for several decades and different models have been suggested to estimate their improved shear strength. The shear strength of such composite materials is affected by the micro and macro mechanical characteristics of both the fibres and the soils (e.g., relative sizes of fibres and soil grains, fibres aspect ratio, stress state, mechanical properties of the fibres), yet no model is available to explicitly take all of them into account. The aim of this work is to establish a new expression for the shear strength of the reinforced material, able to consider the main characteristics of the soil and the fibres as well as the effect of fibre to grains relative dimensions. Data from triaxial tests carried out on fibre reinforced soils with distinct grain size distributions (from clayey sands to sandy gravels) and from previous experimental works were considered and have been analysed successfully within the proposed framework.
