Evaluation of the New Technique of Geogrid-Reinforced and Pile-Supported Embankment at Bridge Approach

Differential settlement between the bridge approach embankment and bridge abutment is a major issue in bridge engineering. To mitigate the differential settlement, a new ground-improvement technique, a fixed-geogrid-reinforced and pile-supported embankment (referred to as a FGT embankment) was proposed. To investigate the performance of the FGT embankment, a numerical analysis was performed for a trial bridge approach embankment in Changzhi, China. The numerical model was carefully calibrated to ensure good representation of the realistic conditions. The comparison analyses and parametric study were conducted to evaluate the effects of the traffic load, long-term tensile stiffness of the geogrid, and long-term elastic modulus of the soil. The results show that the FGT embankment can reduce the settlement, enhance the stability, and offer a better performance measure for the construction of a high embankment at the bridge approach.