Issue 10

Mr. Workman: The problems associated with the design of freestanding multi-flue chimneys within a windshield are of design and functional parameters which often act in opposition and invariably demand an acceptable compromise. A successful compromise can only be achieved by the active co-operation, at design stage, of the architect, the mechanical engineer and the structural engineer.

A symposium was organized by the Institution in London from 17-19 May 1966 on the subject of Industrialized Building and the Structural Engineer. Following this, two ad hoc committees were appointed by the Council to prepare reports Stability of modern buildings and Design for indusfrialproducfion. The first of these was introduced at a meeting of the Institution on 27 January 1972 by L. R. Creasy. The second was completed shortly after the 'Stability' report and was published in November 1971.

An improved formula, intended for the design ofice, is presented for estimating the shear strength of reinforced concrete deep beams and for designing their web reinforcement. F.K. Kong, P.J. Robins, A. Singh and G.R. Sharp

Reproduced herewith are the four parts of the new Rules of Conduct which from 1 October 1972 replace all previous Rules of Conduct and, in particular, those dated 1 October 1964.

The paper examines the lateral stability of beams which are supported at points within their length by elastic restraints capable of providing lateral, torsional or combined restraint. Relationships are provided between the buckling load and non-dimensional lateral and torsional restraint stiffness parameters. The increase in stability resulting from the use of bracing capable of providing both types of restraining action is shown fo be considerable, restraints only a few times as 'stiff' as the beam itself being capable of providing 'complete support' i.e. inducing nodes at the restrained cross-sections. Charts are presented which give the theoretical limiting values which the restraint stiffnesses should have in order to provide 'complete support'. For torsional restraints the influence of the method of attachment is also considered in some detail. D.A. Nethercot and K.C. Rockey