Deep-water quay walls and cost-effective medium- or shallow-water quay walls are in demand at many construction sites since recent times. For works on land, the reinforced soil wall method is adopted; in this method, reinforcement material such as a geogrid is connected to a plate-forming wall and embedded in the backfill ground. This background helped conceive a new structure of sheet-pile quay wall reinforced by geogrids. Deep-water quay walls can be constructed at low cost, and the construction cost of the sheet-pile quay wall may be reduced because geogrids are used instead of costly pile anchorages. This study attempted to solve the problems in the practical use of the new structure via pull-out tests, large-scale loading model tests, centrifuge model tests, and finite elements analyses. The design method and execution process were proposed in this study. The results of model tests showed that an adequate shear resistance force was generated for geogrids even in loose rubble ground. Geogrids reduced the displacement of sheet piles and enhanced the seismic resistance of the quay wall. Additionally, they pulled sheet piles and restrained the active failure of the backfill ground. Through a trial design, the efficacy of the proposed method was verified.

Key Words: reinforced soil wall, geogrid, sheet-pile, large-scale model test, centrifuge model test, finite element analysis