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The objectives of this paper are to present the results of experimental study and analysis on the behaviour and the strength of reinforced geopolymer concrete slender columns. The experimental work involved testing of twelve columns under axial load and uniaxial bending in single curvature mode. The compressive strength of concrete for the first group of six columns was about 40 MPa, whereas concrete with a compressive strength of about 60 MPa was used in the other six columns. The other variables of the test program were longitudinal reinforcement ratio and load eccentricity. The test results gathered included the load carrying capacity, the load-deflection characteristics, and the failure modes of the columns. The analytical work involved the calculation of ultimate strength of test columns using the methods currently available in the literature. A simplified stability analysis is used to calculate the strength of columns. In addition, the design provisions contained in the Australian Standard AS3600 and the American Concrete Institute Building Code ACI318-02 are used to calculate the strength of geopolymer concrete columns. This paper demonstrates that the design provisions contained in the current standards and codes can be used to design reinforced fly ash-based geopolymer concrete columns. [ABSTRACT FROM AUTHOR]

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]

Three different methods of design for reinforced concrete horizontally curved beams are investigated. Tests were carried out on three beams designed by these methods. The beams were completely fixed at the supports and subjected to a vertical point load. The suitability of the design methods is discussed on the basis of observed behavior, strength, and modes of collapse, and by comparing the amount of steel required in each beam. [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]

A simple expression for the calculation of final deflections of reinforced concrete flat slab and flat plate floors is proposed. The deflections calculated by the proposed expression agree closely with those measured in real buildings. [ABSTRACT FROM AUTHOR]

Reinforced concrete structures are capable of significant redistribu-tion of internal forces between the uncracked state and maximum load. Results obtained from tests on large-scale models of edge panels of reinforced concrete flat plate floors subjected to uniformly dis-tributed vertical load are presented. Test results showed that between the uncracked condition and the maximum load there was a consid-erable redistribution of moments, the two support moments and the midspan moments varying by about 50 percent. This suggests that in the design process, any analysis involving a high degree of refine-ment is quite unnecessary and bears no relation to reality. The tests also indicated high moment intensity opposite the column face with a substantial drop in moment just beyond. Based on this study, simple rules for the design of reinforcement in edge panels of flat plate floors are proposed. [ABSTRACT FROM AUTHOR]