Experimental Study of Axially Loaded Sheet Pile for Short-Span Bridge Abutments

Sheet piles have been widely used for water-crossing bridges to mitigate scouring issues and protect backfill soils. Recently, several studies suggested that sheet piles may be able to serve both as axial load-bearing elements and backfill retainers for short-span or low-traffic volume bridges. In this background, this study conducted modified static pile loading tests using a down-sized model test pile at a field test site to investigate the axial load-bearing capacity of the sheet pile. The field test data indicate that the side-frictional resistance would carry a major portion of the applied load (>70%), highlighting its importance in the sheet pile's axial load-bearing capacity. Upon that, this study compared results from the analytical methods, SPT-based methods, and CPT-based methods with the bearing capacity obtained from the field loading tests to assess the suitability of those predictions. For the side frictional resistance, the analytical and CPT-based methods may provide values that are in good agreement with field data, while SPT-based methods may yield quite divergent results. For the end-bearing resistance, most methods employed in this study underestimated the end-bearing capacity. Thus, it may be recommended to account for plugged areas to yield a more accurate prediction of the end-bearing capacity.