Arch bridges will produce horizontal internal force at arch springing under vertical load. The horizontal internal forces and displacement of abutments have significant influences on structural behavior of arch bridge, which was located at soft soil foundation. One of the effective methods to solve the problem is applied the pre-pushing technique behind abutment by two horizontal anti-slide slab. However, there is soil creep deformation at the arch springing under the long-term vertical load. Therefore, an unequal interval multivariable grey model was established to predict the soil creep deformation. This grey model was extended by a single point and equal interval model. The modeling steps are also proposed in this paper. And then the calculated results by the proposed model will compared with the measured results and the results of Burgers model. The compared results showed that it can precisely and effectively predict the amplitude of the creep deformations.