Assessment and retrofit of 3 parking structures in accordance with the ASCE 41 standard is discussed in this paper. All were built between the mid 70-s and early 90-s, and are of cast-in-place reinforced concrete construction. Together with configurational anomalies, columns that are not part of the seismic force resisting system, and are not detailed for deformation compatibility, generally limit the performance of these structures. During design Supplement 1 to ASCE 41 was developed and published, and adopted on the project. Changes to the column modeling and acceptance criteria affected design decisions, and early adoption of the provisions provided a more economical design meeting the requested performance objectives. Foundation flexibility effects are included in the analysis to better predict displacement demands, and confidently assess the acceptability of the performance.
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