Applying design-dependent knowledge in structural engineering design

Abstract

Recent knowledge-based expert systems for structural engineering design have focused on design-independent knowledge (abstract reasoning rules for designing), and while great strides have been made in that area, there is still a significant need to develop systems to take advantage of the wealth of knowledge contained in every substantial structural design. On the other hand, previous database-oriented design efforts have focused primarily on knowledge-poor databases of solutions, in which the traditional engineering handbook of solutions has simply been replaced by digital data. The challenge is to find a way to capture and apply the kind of case-based, design-dependent knowledge that structural engineers have traditionally used. The long-term results will be better structural designs and better structural designers. This paper discusses the character of the design-dependent knowledge in a structural engineering context, describes two initial applications of case-based reasoning to component design, and presents a general paradigm for a knowledge-based design system integrating rule-based and case-based reasoning.

Recording and reuse of design strategies in an integrated case-based design system

“…In our own research program, we have experimented with two small prototypes: FIRST (Daube & Hayes-Roth, 1989;Howard et al, 1989), a system that redesigns structural beams by transformational analogy using a case memory of solution plans, and RESTCOM (REdesign of STructural COMponent) (Rafiq, 1989;Howard et al, 1989), a Prolog-based research prototype for experimenting with similarity and matching in a small case base of reinforced concrete beams.…”

“…On the other hand, design plans associated with particular design cases are an important part of what we call case-dependent or project-specific knowledge (Howard et al, 1989;Howard, 1991;Wang & Howard, 1988, 1991a, 1991b. Case-dependent plans are the strategies used to solve particular design cases.…”