Applying qualitative reasoning techniques for analysis and evaluation in structural design

The authors discuss the qualitative reasoning methodologies for analyzing building structures during the preliminary design process. The objective is to build a general tool, an interactive design assistant (IDA) that focuses on the analysis and evaluation aspects of the design process (as opposed to being an automated decision maker). This framework covers a wide variety of situations in the design spectrum. The framework performs the synthesis-analysis-evaluation iteration qualitatively at different levels of abstraction. Trends observed by simulating the effects of changes in design parameter values at a level give useful directions to refine an existing design. The QSIM approach developed by B. Kuipers (1986) models the feasibility, compatibility, and optimizing constraints as a set of qualitative differential equations. QSIM builds a tree of possible behaviors of the mechanism, starting with an initial state defined by an operating region and a set of qualitative values for the physical parameters. Qualitative simulation makes explicit interactions among structural parameters based on which appropriate design choices can be made