Abstract: The geosynthetic reinforced soil technology used in mixed reinforced soil abutment can shorten the bridge span and improve the overall performance of the abutment. To study the influence of reinforcement spacing, horizontal constraint of wall toe and way of geogrid around pile on abutment deformation, as well as the influences of road surface load, four static load model tests are carried out. The results show that the mixed reinforced soil abutment is stable and the overall deformation is small under the pavement load. The monitoring results show that the existence of pile in the reinforced soil abutment reduces the lateral deformation of the abutment. The existence of horizontal constraint of wall toe can limit the deformation of abutment, while reducing the reinforcement spacing and way of geogrid around pile with rigid casing can enhance the stiffness and integrity of the reinforced soil, reduce the horizontal displacement of the wall face and improve the working performance of the mixed reinforced soil abutment. The research results have reference value for the engineering design of mixed reinforced soil abutment.

Key words: geosynthetics, reinforced soil abutment, deformation, reinforcement spacing, horizontal constraint of wall toe, way of geogrid around pile