Gasholder Development and Design Discussion on the Paper by Mr. W. R. Garrett

THE PRESIDEST, introducing Mr. G. M. Boyd, said he was able to speak with considerable experience on brittle fracture problems in steel construction, a subject which had been with us for a long time and which had become of very considerable importance within recent years.

THE importance of being ablc to calculate the critical load of a strut has long been recognized, and a considerable part of any modern design code is devoted to this end. However, progressive structural engineers are dissatisficd with a design process in which it is necessary to consider the stability of a stanchion as though it were isolated from the frame. When this is done no exact allowance can be made for the stiffening effect of adjacent members or of the redistribution of moments which takes place as the axialoads in mcmbers are incrcased. It seems likely that a rational design method can be developed using the critical load of the complete frame as one parameter. This paper demonstrates a method of obtaining the critical load of building frames in which sway can take place and includes approximations which are believed to be accurate and quick enough for use in such a design. Arthur Bolton Arthur Bolton

This month's letters cover legislation for design checks, embodied carbon of modular construction approaches, and assessment of masonry buildings for earthquake resilience in New Zealand.