Polyamide-fiber laid-strand ropes are candidates for the shallow-water mooring lines of the future floating offshore wind turbines. Their mesoscopic scale follows a hierarchical architecture: subrope, strands, rope-yarns, yarns, filaments. Their mechanical behavior is the result of friction between components and the visco-elasto-plastic behavior of the filament material. Under cyclic loading, fatigue damage based on the component frictions occurs and is a matter of concern for a 20-year service life. Friction phenomena at the different scales are difficult to quantify experimentally, so we adopted a modeling approach for understanding the friction behaviour. We applied Charmetant’s model for describing the deformations within the subrope at the scales of the strand and rope-yarn. Actually, the subrope will be modelled by the quasi-static FEM as three helical strands in contact with each other. Each strand will be meshed by volumic finite elements; at integration points a user-routine behavior law is implemented. As Charmetant et al. showed, this behavior law will distinguish the friction strain modes from the filament material strain mode within the global deformation gradient undergone by the bundle of rope-yarns. For each of these strain modes, a dedicated and relevant behavior law is proposed. Experimental tests are used to identify the model parameters, while, by using other dedicated experimental results, we can afford to test or validate the model predictions.