Structural Design Iteration: The Application of DSM to Seismic Retrofit

Iteration in design or re-design is commonplace within architectural, engineering, and construction (AEC) projects. Positive iteration is often required to optimize design solutions around competing objectives. This runs counter to the misconception shared by many engineers that iteration is negative and linearity in design is preferable and achievable through adequate pre-planning. We have identified a void in the practical application and theoretical development of design theory within the structural engineering community, particularly in methodologies that address iteration in design. This void points at a lack of understanding that contributes to project performance deficiencies as characterized by cost over-runs and sub-optimal design, among others. This paper presents a seismic retrofit case study for the purpose of developing a greater understanding of the role of iteration in design. The design structure matrix (DSM) work planning tool is used to optimize the sequence of design activities in order to limit the required impacts of necessary iteration allowing for efficient information flows. The implementation of DSM on this project had two valuable effects: (1) the optimized matrix correctly identified the dependency network underlying the primary design problem as evident by the alignment of observed iterative activities and the derived block, and (2) the DSM provided a common framework for discussing iterative tasks and planning collaborative design efforts within the multi-disciplinary team.