Effect of Specimen Size on Flexural Behavior of Doubly Reinforced Concrete Beams

Effect of Specimen Size on Flexural Behavior of Doubly Reinforced Concrete Beams
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© 2023 by IJETT Journal
Volume-71 Issue-8
Year of Publication : 2023
Author : Chatikam Chandra Mouli, G. V. Rama Rao
DOI : 10.14445/22315381/IJETT-V71I8P215

How to Cite?

Chatikam Chandra Mouli, G. V. Rama Rao, "Effect of Specimen Size on Flexural Behavior of Doubly Reinforced Concrete Beams," International Journal of Engineering Trends and Technology, vol. 71, no. 8, pp. 168-175, 2023. Crossref, https://doi.org/10.14445/22315381/IJETT-V71I8P215

Abstract
Material strength is a random variable that is a statistical distribution of strengths that varies from point to point in the material. As the size of the structural element increases, the probability of encountering a fault or discontinuity in the material also increases, which leads to a reduction in the overall strength of the element. Hence, it is important to understand the relationship between specimen size and the strength of the material. The studies conducted by past researchers are mostly on the effect of beam specimen size on the shear performance of RC concrete beams. Further, very few studies were available on the effect of specimen size on load vs deflection behavior, Absorbed Strain Energy and Toughness index of doubly reinforced concrete beams. It is concluded from the study that the First crack load, Deflection at First crack load, Peak load and Fracture load, Deflection at collapse, Deflection at Peak load, Displacement ductility ratio, Strain energy absorbed up to first crack, Total Strain energy absorbed, Experimentally determined Moment of Resistance at peak load, Ultimate Moment of Resistance calculated as per IS 456 2000 and Toughness index at first crack load increase with increase in dimensions of specimen. However, the factor of safety decreases with an increase in specimen size.

Keywords
Specimen Size effect, Load vs deflection behavior, Peak load, Fracture load, Toughness index, Strain energy absorbed, Displacement ductility, Moment of Resistance

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