This paper describes the numerical modeling of geosynthetics-reinforcement mechanism in soil structures. The confining effect brought by the geosynthetics working so as to prevent dilation of soils is considered by introducing constitutive models that can express dilation of soils with shear. Then, the deformation-failure behaviors of two full-scale geosynthetics-reinforcement soil structures are simulated using the finite element computation technique. Herein, the compacted soils are treated as saturated-heavily over-consolidated clays and the determination procedure of input parameters needed in the models is proposed. Numerically predicted behaviors are compared with monitored ones.