IIW History 1948-1958

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progress of its work, the programme of which had been drawn up at Oxford , resulted finally in the Commission again becoming autonomous from the time of the Goteborg Assembly in 1952, when its terms of reference were finally agreed upon and when Mr. DE LEIRIS (France) became Chairman.

It was generally agreed at Goteborg that the te_rms of reference of the Com- mission should cover : all metals and alloys which could be joined by welding, all welding processes, autogenous or not, and all allied processes, such as oxygen cutting, etc., m so far as they could affect fatigue strength. Apart from tests on specimens, assemblies and structures, the Commission put on its programme of work, because they directly affect the practical signi– ficance of fatigue tests, the systematic study of failures in service, about which it hoped to receive as much documentary information as possible. The Commission agreed that the ultimate objective of its \vork \Vas to con– tribute towards a definition of the conditions under which welded assemblies with the highest degree of fatigue strength can be produced. These terms of reference necessitate liaison with other II\V Commissions, in particular with Commission V (Testing, Measurement and Control of ·welds) a nd Commission XV (Fundamentals of Design and Fabrication for \Velding). At each of its meetings Commission XIII deals with activities of two kinds. Firstly, members each year exchange information about investigations under– taken in their countries on the fatigue of assemblies or welded constructions; they report on the work carried out or give information about proposed pro– grammes of work. S.uch exchanges of information have several times lead to useful discussions which have resulted either in the amendment of the programmes discussed or in several members collaborating in carrying out these programmes. Secondly, the Commission examines reports on subjects which it was decided to study at the previous Assembly. There are many such subjects. This is accounted for by the fact that, with programmes of fatigue testing, it generally takes a long time to carry out and complete the work so that it is not always possible to reach a conclusion between two annual assemblies. Thus a given subject \Nhich the Commission may discuss and decide to study at one assembly is not necessarily on the agenda the following year but is only discussed again two or three yea rs afterwards when sufficient information about it has been collected. Finally, for the last few years, the Commission has discussed and prepared for publication documents reaching it as a result of an investigation which it undertook on fatigue failures in service, which is described below. Unlike the majority of the other Commissions, Commission XIII has no ub-Commissions; the essential part of the work is carried out by correspondence between the annual assemblies. For special subjects, some members may he appointed to form a ·working group; such has been the case for the statistical interpretation of fatigue tests and for the preparation of a programme of fatigue test s on butt welds. 2 . ORGANISATION AND WORKING METHODS.