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Enlarged (Type II) pile shaft foundations are used frequently in reinforced concrete bridges because of the convenience in construction and efficiency in post-earthquake inspection and repair. According to the specifications of the California Department of Transportation (Caltrans), the diameter of a Type II shaft should be at least 610 mm (2 ft) larger than that of the column. Hence, the column reinforcement extended into the pile shaft can be perceived as forming a non-contact splice with the pile shaft reinforcement. Because of the lack of data, the seismic design specifications of Caltrans on the embedment length of column reinforcement in Type II shafts are very conservative for large-diameter columns, which could complicate the construction work and entail high construction costs.