Evaluation of Behavior of a Laterally Loaded Bridge Pile Group under Scour Conditions

Scour in the vicinity of bridge piers may result in a reduced capacity of bridge foundations. A complete study of bridge stability under scoured conditions requires integration of water, soils, pile systems, and bridge superstructure analyses. This paper describes an analysis performed in which soil and pile group interaction was evaluated using the Group Equivalent-Pile (GEP) method. A pile foundation supporting Kansas Bridge 45 was studied to evaluate its lateral behavior under scoured conditions. Effects of scour depth and pile head boundary conditions on the total deflections of the pile head and pile deflection profiles were examined. Results showed that scour reduced the lateral capacity of the pile group, especially when the scour depth was below the depth of the pile head. In addition, scour changed the influence depths of the deflection, bending moment, and shear force of the pile group.