BOUNDARY ELEMENT ANALYSIS OF THIN PLATES INTERNALLY BOUNDED BY RIGID PATCHES

Procedures are described for modelling a structural system consisting of thin Kirchhoff plates with internal patch areas capable of displacing as rigid flat surfaces. The physical prototype for these patches could be interconnection points for one-dimensional frame type elements of various shapes and layout. rigidly connected at these finite size `joints' in the plate. The numerical procedure for modelling the thin plate is the Direct Boundary Element Method (DBEM) and a simple overview of this procedure is provided. Potential trouble spots, of which the user should be aware. are described. The paper will be of interest to structural engineers for analysis of frames having both plate and simple frame elements. for example, building frames: and also to researchers seeking the greater detail that this refined procedure can provide. As a practical tool the methods described are computationally competitive with existing procedures, including the more rugged approaches used by building structural engineers for dynamic and torsional analysis.