TR012: Structural Steel Framing Data Model

This report describes an object -oriented data model for structural steel framing. The model was developed by Mr. Ajay Lavakare, a graduate research assistant in the Civil Engineering department, working under the supervision of Professor H. Craig Howard. The work was part of the "Multiple Views of AEC Data" project supported by the Center for Integrated Facility Engineering (CIFE) at Stanford University.

The purpose of the model is three-fold:

1) To gain a better understanding of the problems of representing complete design data in an object-oriented model. We have worked on relational data models for steel structures and found them insufficient to represent both the relationships between structural entities and the varying degrees of abstraction necessary to reason intelligently about the structure (e.g., abstractions like "element" and "node") in addition to the physical elements (e.g, "beam" and "bolt"). Eventually, we hope to apply the ideas from this project to the development of a complete, object-oriented, integrated data model for CIFE applications.

2) To gain a better understanding of the PDES standard for data exchange. Our starting point was the current draft version of the PDES standard, and our starting question was "How can we apply and adapt these ideas to our data representation problems?" In the architecture, engineering, construction (AEC) domain, very few areas have been attacked in any breadth or depth. We hope that the structural steel data model and our subsequent models may eventually contribute to PDES Professor Howard is a member of the ABC committee of the PDES organization.

3) To reinforce our KADBASE applications. KADBASE is a flexible, knowledge-based interface in which multiple engineering applications and databases can communicate as independent, self-descriptive components within an integrated, distributed engineering computing environment. A key element of the KADBASE architecture is a global data model that integrates all local data models. The structural steel model is our first attempt at building an a priori global model, and it helps us to verify the data representation capabilities of the KADBASE prototype software.