Application of a state-dependent hyperelastic-plastic constitutive model for slope stability analysis of fiber-reinforced sand

Fiber-reinforced soils are widely used in the field of geotechnics to enhance slope stability. Still, proper consideration of fiber inclusions for slope stability analyses remains challenging since advanced consti- tutive models for fiber-reinforced soils can usually not be used for slope stability analyses. The main reason for this is that popular methods to investigate slope stability, for instance limit equilibrium method, limit analy- sis or strength reduction finite-element analysis, are mostly restricted to the use of simple constitutive models. Thereby, shear strength and dilation response of reinforced soil assemblies cannot be properly captured. In this study, “strain-dependent slope stability” (SDSS) is used to evaluate the stability of fiber-reinforced soil slopes as it allows the use of sophisticated constitutive model for slope stability analyses. For this, a new hyperelastic- plastic model has been developed that incorporates a new state parameter influenced by fiber inclusion. For validation of the model, simulations in element scale are compared with experimental data of triaxial tests. Af- terwards, the model is implemented in ABAQUS as a user-defined material routine for slope stability analyses. To show the capability of the new approach, slope stability analyses are conducted for fiber-reinforced soils, considering variations of fiber content.