Dr. Le-Wu Lu (Research Associate-Professor of Civil Engineering, Lehigh University, Bethlehem, Pennsylvania) writes:- 'The authors are to be congratulated for contributing an interesting paper in an area which has attracted considerable attention in recent years. The use of computers in elastic-plastic analysis provides not only the potential of dealing with highly complex structures but also the capability of inclusion of many so-called "secondary effects". The program developed in the paper has attempted to include almost all the major secondary effects, except, as the authors noted, the following two:- (l) the effect of reduction of plastic moment (2) the spread of plastic zones in the members.
This paper describes tests that have been carried out to determine the long-term deformation characteristics of Lytag lightweightaggregate concrete, in axial compression and deflection; comparisons are made with gravel concretes made from London-area aggregates. Professor R.H. Evans and W.S. Paterson
Architecture and civic design face serious problems of location, structure and accessibility, arising from the condition of crowded urban societies in every part of the world-even the newly developed: unprecedented increases in numbers, rapid technological advance, greater mechanization and new concepts of space and scale; but less corresponding capacity, as yet, to adapt social institutions and controls to cope with accelerating population and growth rates: more affluence and leisure on the one hand, and on the other a growing majority of people inadequately fed and housed. There is thus a universal migration into cities coupled with a deterioration in urban environment; as the vehicle ousts the pedestrian, utilities replace the monument and advertisement-commercial and public-camouflages the noticeable parts of the civic structure and furniture which man has already designed for purposes of living, working, playing and meeting his fellow-men. William Holford
In the past few years the first Ordinary Meeting of the New Year has been given over to a discussion or debate on a theme of topical interest to structural engineers. Against the background of the much-publicized structural collapses of 1966 the meeting on Thursday 12 January at 6 o’clock to debate the motion ‘ That structural design is best carried out in professional offices ’ will provide an opportunity for airing members’ views on these events.
Mr. Peter Dunican, introducing his paper, said that the title ‘ The art of structural engineering ’ had been chosen quite deliberately because, although it was a matter which he might not be able to pronounce upon too clearly, it was a subject which as a practising structural engineer he ought to know something about.
The Joint Building Group was formed in 1963 and exists to improve efficiency within the building and construction industry by promoting interprofessional discussion on common problems.
The Craigellachie bridge, over the River Spey at Craigellachie, Banffshire, was originally designed and constructed in cast iron by Thomas Telford in 1814-15. It was reconstructed in 1963-64 to make it capable of carrying modern traffic not greater than 14 tons the bridge, it was essential to keep as much of the original character in weight. In addition, it was recognized that, in reconstructing as possible; when a new bridge is constructed nearby, the cast-iron bridge is to be restored to a condition which will enable it to be retained for as long as possible as a monument to Thomas Telford and his work. W.W. Lowson