An integrated system for foundation design of building structure is developed. The types of foundation and the allowable bearing capacity inferred by the rule based foundation type selection system, SOFTEX (Selection of Foundation Types Expert System), are transferred to BUILDS-F that is the foundation structural design subsystem of BUILDS.
SOFTEX is implemented with the expert system building tool, CLIPS (C Language Integrated Production System), and external functions and applications. The foundation types such as independent spread footing, wall footing, combined footing and mat foundation are inferred by following procedure. The foundation type is assumed as an independent spread footing and the footing size of each column and wall is calculated. Each footing is tested whether this one is overlapped with another. If two footings are overlapped, those overlapped footings are merged by the foundation merge technique developed in this study.
The variable node plate bending element is used effectively in the analysis of a mat foundation. The variable node elements can generate a nearly ideal grid for mat foundation analysis in which more nodes are defined near the column location where the steep stress gradient is expected. Several mesh schemes were proposed and tested in order to find the most suitable scheme for mat foundation analysis. The data file for the finite element analysis of mat using variable node plate bending element is automatically generated with search technique that has been studied in AI field.
By using this integrated system, the structural engineers with less experience in foundation design can design the foundation system for the given superstructure and the site condition with relative ease.