THE THEOREMS OF STRUCTURAL VARIATION GENERALIZED FOR RIGIDLY JOINTED FRAMES.

The theorems of structural variation are extended to cover the case of rigidly jointed frames. Examples are given to show how it is possible, without a fresh analysis, to obtain the forces and the deflections throughout a frame from the results of a different parent frame. The procedure is so simple that the calculations are often carried out manually. The application of the theorems to the analysis of frames with a non-linear moment curvature relationship and to the elastic-plastic analysis of frames is given with examples. Structural variation in the topological design of a highway bridge is then used to achieve minimum cost. The results of an investigation are then presented to show that, by structural variation, it is possible to analyse frames consisting of members of variable cross-sections from the results of a single analysis of a frame with prismatic members. Practical examples are given to show the versatility of the theorems.(a) /TRRL/