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The Structural Engineer

Failure of beam-columns subjected to axial compression, transverse loading, and unequal end moments, is investigated. A formula is proposed to predict the failure load of such beam-columns. Derivation of the formula is based on the concept of interaction between the two modes of failure, i.e. elastic buckling and plastic collapse of the beam-column. D. Ho

The Structural Engineer

There are at present no design data on the shear resistance of reinforced concrete T-beams made with UK lightweight aggregates and natural sand. This paper presents comprehensive test data on the shear strength of T-beams without web reinforcement and made with Lytag coarse aggregates and sand. The effect of three parameters, i.e. concrete strength, steel percentage, and a/d ratio on shear strength, is reported. R.N. Swamy and G.H. Lambert

The Structural Engineer

Helical rectangular beams with fixed ends are defined as beams circular in plan and supported only at their ends. They are in general 3-dimensional structures indeterminate to the sixth degree. In the present study, helical slender beams of rectangular sections with a width-to-height ratio of b/h ¡Ü 0.50, are analysed as linear symmetric structures loaded vertically by uniformly distributed dead and live load. The principle of virtual work1.2 is used for the analysis by choosing the appropriate release system to arrive at final expressions, which are solved using appropriate design charts drawn for two basic types of structure (a) wide beams b/h ¡Ý 0.5 and (b) narrow beams b/h ¡Ü 0.50. Professor G.D. Stefanou