Optimal Design of Flexural Systems: Beams, Grillages, Slabs, Plates, and Shells

Abstract

Professor Troitsky treats the technologically important subject of orthogonally stiffened plates. As he says, books on the subject are scarce. He provides a large amount of information from the literature. Hundreds of references are cited. Historical reviewing is attempted, but it is not carefully done. A weakness of the book is the lack of an experimental foundation. True some experimental results are cursorily supplied, but a basic comprehension of the physical nature of the problem is absent. The present reviewer recalls his own dissatisfaction with the doctoral dissertation of Schade, on stiffened inner bottoms of ships, which he wrote in Germany under the followers of the Huber school. Schade used a purely analytical method to calculate rigidities. Trying to put such calculations on a better basis, Huffington, under the reviewer's direction, calculated rigidities using the theory of elasticity. This work is mentioned by the author. It was not until the reviewer saw the Bergstrasser experimental method that he himself devised an experimental program for the determination of equivalent orthotropic elastic constants. It became apparent to him that the Huber concept could be extended to the study of large deflections of plates and to shell deformations, if he experimentally determined both the bending and twisting constants and the stretch and shear of middle surface constants. His definitive experiments are described in the 1956 Proceedings of the Society of Experimental Analysis. The large deflection studies of W. G. Soper, also mentioned by the author, are based on these experimental results. Incidentally, the elastic rotational edge constraints were provided experimentally. For the purpose, a suitable device was required. It is described in a Note on the "Boundary Conditions for Bending Experiments With Bars and Plates," by the reviewer and Soper in the

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