Differential settlement in splicing region in embankment widening always causes breakage to the pavement, the global stability of the embankment can be improved and the differential settlement can be reduced in splicing region of embankment by geogrid reinforcement. And the working mechanism of geogrid reinforcement was introduced basing on the investigation on the causes of common problems in road widening project. In addition, the finite element method soft package PLAXIS was employed to calculate the tensile forces and displacements of the top and bottom geogrid layers after the process of the newly widened embankment construction. The contact element based on Coulomb criterion was adopted to describe the performance of reinforcement-soil interface during the calculation, and the variation law of geogrid tensile forces under different pavement surface load was also analyzed. The tensile force, the settlement and the lateral displacement of geogrid were calculated with the changed influencing coefficient of geogrid-soil interface. The results show that the displacement and the tensile force of the bottom geogrid layer are the biggest, and the tensile force of the geogrid gradually reduces to be zero from the junction point to the point further than 4 m from the junction. Moreover, the tensile forces of the geogrid layers increase with the vertical load on the pavement surface, and the peak value of the tensile forces decreases with the influencing coefficient of geogrid-soil interface.
