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Limitation of long-term deflections is an important consideration in the design of reinforced concrete flexural members. An expression is developed for maximum allowable span-depth ratios for reinforced concrete beams and one-way slabs. The derivations are based on Branson's deflection computation method recommended by ACI 318-77. Both the total deflection as well as the incremental deflection that may occur after attachment of nonstructural elements are limited. Finally, numerical examples are included to illustrate use of the proposed equations. [ABSTRACT FROM AUTHOR]

Tests on 22 prestressed concrete I-beams are re-ported. Most beams were tested in bending and torsion, but -four also carried shear. Seven beams had reinforcement linking the flanges to the webs, and fifteen had no such reinforcement. Strength theories are developed for both types of beams. It is concluded that flange reinforcement in I-beams is essential since without it the flanges add little to the strength of the web alone, and may even be detrimental. Building code rules should perhaps take account of this. [ABSTRACT FROM AUTHOR]

Results of torsion tests on ten rectangular rein-forced concrete beams are presented, the principal variables being aspect ratio and amount of rein-forcement. It is shown that, other things being constant, the strength decreases with an increase in aspect ratio. Equations are derived for ultimate torque and minimum reinforcement. Correlation between predicted and experimental strength is good, not only for the ten beams tested but for sixtyfour others available in the literature. [ABSTRACT FROM AUTHOR]

An approximate method for the calculation of long-term deflections of flat plates and flat slabs !s described. The method is applied to compute deflections of three existing floors for which details are available. The agreement between measured and calculated deflections is good. [ABSTRACT FROM AUTHOR]

Equations developed in an earlier paper for the strength of prestressed beams subjected. to bending, torsion and shear are rearranged m a form suitable for design. A design example is included. [ABSTRACT FROM AUTHOR]