Research on the Application of EPS in Treating Bridge-approach Settlement

Abstract

The differential settlement between abutment and bridge approach embankment can be reduced by replacing a certain thickness of the bridge approach embankment with EPS geofoam, but the design approach of this technique is not yet comprehensive. In light of this, a long-term settlement prediction model of embankment was obtained on the basis of the field monitoring data of a similar actual project, according to which a numerical model was also established by using the Cvisc visco-elastoplastic mode in FLAC3D and its availability was verified by comparing the results from field monitoring and numerical modeling. Finally, the settlement curves of embankment, the treatment effect and the design parameters of EPS were discussed by numerical simulation. The results show that the differential settlement could be effectively controlled by using EPS in the improvement engineering of bridge approach embankment owing to the less gravity of EPS, and the application effect becomes more and more significant, e.g., approximate 40% of the settlement could be reduced at 3 000 days after construction. The settlement of road border is slightly less than that of the center line in bridge approach embankment, which should be considered in the design owing to its adverse effect on road surface drainage. The pavement settlement would decrease linearly with the increase of EPS density, but its decreasing trend is abated gradually with the increase of EPS filling ratio. As a result, EPS material with high density could be selected for replacement in a certain range of thickness-ratio in engineering designing.

Keywords

• bridge approach embankment
• settlement
• expanded polystyrene geofoam
• creep effect