Joint Meeting

THE PRESIDENT (Mr. F.E. Drury, M.Sc., M.I.Struct.E.) said that no doubt the members knew something about the strength of aluminium structures, but they did not know a great deal, perhaps, about aluminium and its alloys. The paper gave them an opportunity, therefore, to broaden their minds on this subject, especially from a metallurgical point of view.

But for the war the election of Professor John Collins as President of the Institution of Structural Engineers would have taken place several sessions ago. For the six years from November 1939 until September 1945 he was out of action as far as the Institution was concerned, being on active service in the wider sphere of the Second World War-and for the second time in his career. For that reason, his name may not be so well known to the younger members of the present generation as it is to their immediate predecessors.

Whilst it has been accepted since the days of Considere's work at the beginning of the century, that a helical form of lateral reinforcement increased the strength of a reinforced concrete column, so far as the Author is aware, it has never been claimed that the ordinary hoop form of binder gives any material contribution to the ultimate strength of the column. This Paper, amongst other points, submits the results of tests to destruction of nearly 200 small columns, and indicates quite definitely that the normal binders, if placed at a sufficiently small pitch, can contribute considerably to the load carrying capacity. It also questions the currently accepted practice of ascribing the helical binder effect to its function in restraining the lateral expansion of the concrete. Jeffrey William Hitchen King