Earthquake-induced liquefaction is likely to cause uplift displacements of underground structures and excessive settlements of surface structures. While these two phenomena have been investigated separately in the literature, the case of a shallow tunnel buried adjacent to a surface structure in liquefiable ground remains to be thoroughly studied. In this paper, the OpenSees platform is employed to numerically model two centrifuge tests on the structure-soil-structure interaction in saturated Hostun sand. The PM4Sand constitutive model is calibrated to capture the nonlinear behavior of the liquefiable ground. Overall, the numerical simulations are in good agreement with the centrifuge test data. The excess pore pressure build-up, the acceleration response of the Hostun sand ground, the uplift of the tunnel, and the settlement of the surface structure are simulated with adequate accuracy. Then, the validated numerical models are used to further investigate the structure-soil-structure interaction in liquefiable ground with a special emphasis placed on the variation of relative density of the sand, and a parametric analysis is conducted on the responses of the tunnel and the surface structure.