IN 1951 the North Eastern Gas Board agreed to the provision of additional gastorage capacity at York. High and low pressure storage schemes were considered and it was finally decided to proceed with the erection of a spirally guided gasholder of approximately 2 million cubic feet capacity. T. Albone and H. E. Manning
STRUCTURAL Engineers are now familiar in general with the work of Professor J. F. Baker and his Cambridge team on the application of plastic design methods to steelwork construction. The object of this paper is to show how these methods can be applied to reinforced concrete. Professor W. T. Marshall
The CHAIRMAN introduced the Authors, and Dr. Lightfoot then presented the paper.
THIS paper describes a new and very simple method for the analysis of two pinned sinusoidal arch ribs. (Since the difference between a sinusoidal and a parabolic profile of the same rise and span is quite small the theory will apply to parabolic arches with reasonable accuracy.) The analysis shows that the bending moment diagram for an arch rib of this type is obtained by subtracting from the simple span bending moment diagram its first harmonic component. It is also shown that harmonic components of the loading higher than the first produce no horizontal thrust and that a system of arch ribs of negligible torsional stiffness interconnected by cross girders which transmit only vertical forces may be analysed as a flat grid provided that the first harmonic of the simple span bending moment diagram or deflection curve, as the case may be, is omitted. Distribution coefficients for grids have been published previously by the Authors. A worked example of the method of calculation is shown and a confirmatory experiment is described in an Appendix. A. W. Hendry and L. G. Jaeger
The CHAIRMAN introduced the Author, who then presented his paper.