Wind-induced Oscillation of Circular Chimneys and Stacks

The paper uses yield-line theory to derive equations and charts suitable for the limit design of uniformly loaded rectangular reinforced concrete slabs with rectangular openings. Four positions of openings are considered: the slab centre, the slab corner, the centre of a short side, and the centre of a long side. The ratios of the corresponding lengths of the sides of the opening and the slab are kept the same and sizes of opening of up fo 0.6 of the length of the slab sides are considered. The edges of the slab are assumed to be either all fixed or all simply supported. Design charts are plotted for various values of the ratio of negative to positive yield moments and for the ratio of the yield moments in the two directions. S. Islam and R. Park Two-way reinforced concrete slabs often contain

The principal theme underlying the paper is the development-from a structural engineering standpoint-of a form of construction for high riseflats, based essentially on ‘factory-made’ components, on the one hand quicker to build than more traditional forms of in situ reinforced concrete construction and, on the other, comparable in terms of cost and also structural behaviour if subjected to an abnormal load.

January 1971 was the first occasion that the Institution examined candidates for corporate membership in the Part 3 Examination only; and the first time that the Technician Test was set. This review of the performance of both groups of candidates is based upon the reports of the respective examiners, all of whom are practising chartered structural engineers with an average age of well below forty.