A contribution to architectural/engineered design for timber structures using knowledge-based methods

This thesis attempts to synthesize knowledge from the fields of architecture, engineering, and computer science in the contest of design. In particular, a novel approach to modeling the architectural and engineering design of structural connections is presented. Computer automation using parametric object-oriented methods for quantitative design is new for connections, and the inclusion of qualitative features native to architectural considerations present a more holistic view to automated design of connections. A unique method of representing connections as a kit of parts for assembly is presented that is based on the load path within the connection. The configuration model facilitates engineering discretization and evaluation; while the connection, if properly designed, can be more easily "read" by the observer--a desirable feature of a good work of architecture. Quantitative aspects, typically thought of as engineering qualities, are combined with the adapted qualitative, typically architectural, aspect of a designed artifact through the use of dynamic fuzzy logic membership functions. A fuzzy logic adaptation of the qualitative attributes of the designed artifact can be used for assessing or generating aesthetics consistent within the scope of aesthetic definitions offered by the designer. The adaptation, therefore, does not constrain the designer to a prescribed attribute definition, but an architectural expression which is personal and unique. A brief development of membership function representation, calibration, and application is offered. Results from a particular demonstrative study of proximity, and another on colour reveal a promising application of fuzzy logic technology to qualitative design issues. Among a number of smaller innovations, the main contribution of this thesis to the advancement of knowledge is three fold: a new method to represent structural connection in general; a synthesis of truths underlying connection configuration design in timber structures so hat design automation using object-oriented method can be facilitated; and development of an automation method for connection design that separates program control from object data, which is a significant benefit in ease of automated application expansion. The work presented here is intended to break new ground in these areas for others to investigate further towards resolving a significant need in design.