Models of binary asteroids based on spherical components are inadequate to analyze lightcurve data, since if the shape is determined by self-gravitation, significant tidal distortions are present. On the other hand, equilibrium binary models proposed so far (e.g. for 624 Hektor and 216 Kleopatra) are based on the arbitrary assumption of equal-sized components. The authors present sequences of equilibrium Roche binaries for values of the mass ratio between 0.01 and 1, and discuss the application of these models to real asteroids. Two items of particular interest are: (1) for asteroids of known rotational properties, the equilibrium models allow to constrain the admissible values of the mass ratio and density; (2) the models allow to describe qualitatively the expected light curve morphology.