Practically all design rules for webplates of steel girders are at present based upon the conception of critical stresses. The solution assumes (a) “Ideal webs,” that is, webs which are perfectly plane before loading, with centrally applied force, and with no residual stress developing. (b) Very small lateral deformations compared with the web thickness. The primary and bending stresses only are considered; the effect of membrane stresses being neglected. C. Sc. Ing
WELLINGTON (NEW ZEALAND) SECTION Hon. Secretary : D. H. Sim, B.E. (Graduate), 31, Field Street, Silverstream, Upper Hutt, Wellington, New Zealand.
In presenting his paper the author said that whilst the paper concerned the structural design and construction of the tower, it would no doubt be appreciated that there were many other aspects of the design, all of which had influenced the structure to a greater or lesser degree. He asked that it be borne in mind that the tower block was only part of the Development, though it did form the greater part-over 50 per cent in terms of floor area and volume. The foundations and superstructure, he said, could be considered quite separately from the adjacent buildings, but architecturally and economically they could not. His introductory remarks were followed by slide illustrations.
An acquaintance with the history of structural analysis greatly enhances the value of a knowledge of structural theory. For the engineering student this is particularly so, with perhaps even greater emphasis in the case of the part-time student whose curriculum is often restricted to statements of basic principles and their applications without reference to origins. P. Carlson
Mr. J.N. WEBB (Associate-Member), asked whether the construction of the bridge in steel had been considered.