Issue 7

Mr J. Maguire (Lloyd's Register) I have several questions on the paper. (1) Could the authors advise the measured damping values? Were these obtained from forced vibration or ambient tests?

John Grant (Viewpoint, 3 October 1989) exhorts us to teach computer analysis and to be inspired to design by sitting at the feet of those such as Professor Sir Alan Harris. He implies that design cannot be taught; we can learn only by example. I too have listened to excellent lectures by good designers, who have opened my eyes to the way design is carried out. But Sir Alan’s adage that ‘design is what is done in the bath, and analysis is the process to prove that design’ is too simplistic. It is worth defining what we mean by analysis and design, before being too specific about what is taught. C.J. Burgoyne

Below is published the ‘Media relations guide’ produced by the Public Relations Panel of the Institution. The panel hopes that this will provide useful guidance to those involved with media contact. The panel would welcome comments on the guide and suggestions which might be incorporated in any future revision. Please address these to the Secretary of the Institution. This guide has been written to assist members of the Institution in recognising opportunities for publicity and promotion in the media and to make them more effective in media approaches.

This paper presents a non-linear finite element procedure for the strength determination of cold-formed box columns. The effects of residual stresses, local buckling, and initial imperfections, are all included in the analysis. The proposed theory is validated and its accuracy assessed against experiments conducted at the University of Sydney. A table for the strength of the sections with various member slenderness (L/r) and plate element slenderness (b/t) ratios is also produced, so that the typical relationship between the strength and these two ratios can be understood. The suggested method can be ufiiised to supplement experiments in the generation of design curves and in the parametric studies of the behaviour of cold-formed hollow sections subjected to various types of loading and boundary conditions. S.L. Chan

The task of selecting an economic but effective paint scheme to protect structural steelwork is specialised and requires knowlege outside that of the majority of structural engineers. For many design organisations, the employment of a paint specialist is not practicable, and resource must be had to outside help. R.J. Allwood and C.N. Cooper