By M D Boltonm S P Choudhury and P L R Pang, The University of Manchester Institute of Science and Technology
This paper was first publsihed in GE’s September 1978 issue
Although designers may be able to conjure almost perfect constructions without the need for formal calculation, they and their clients presumably sleep sounder if they are able to compare their conception with cousins which have previously proved satisfactory. The process of proving in advance the inevitable success of a project is usually degraded to the point where the designer shows that he has excluded features which have previously been shomn to be associated with failures or ‘limit states’. Bad features are often exposed in Codes of Practice.
These logical avenues lead into limbo if the designer feels that he has introduced a completely new form into the world. He must then attempt to create an experimental scheme, win over a few clients, gain experience, and hope to expand his knowledge in a controlled manner. This seems to have been the recent history of Henri Vidal with his Terre Armee, who can now point to the success of hundreds of similar schemes if the safety of his system is called into question.
The responsibility of the research worker is similar to that of the designer. But whereas the designer may draw comparisons with previous manifestations of the actual scheme, the research worker will usually dram comparisons with abstract concepts of mechanics. The research workers will hope to demonstrate that the new form can be safely analysed in terms of simple existing mechanical principles. If so, there is hope that these prin’ciples will allow the refinement of the new technique, will allow its extension more quickly into unproved areas, and will allow a more rigorous analysis of safety than can be gained simply by having not yet made an error in practice. Such have been our objectives.