Influence of nano-SiO2 and nano-Al2O3 additions on the shear strength and the bending moment capacity of RC beams. (1st October 2016)

• Record Type: Journal Article
• Authors: Silva, J.V.; Ismael, R.; Carmo, R.N.F.; Lourenço, C.; Soldado, E.; Costa, H.; Júlio, E.
• Is Part Of: Construction & building materials. Volume 123(2016)
• Page Start: 35
• Page End: 46
• Publication Date: 2016-10-01
• Subjects: Nanoparticles -- Steel fibers -- RC beams -- Shear strength -- Bending strength; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2016.06.132
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: Evaluation the influence of nano-Al2 O3 and nano-SiO2 on shear strength and bending moment capacity. The effects of nanoparticles in the RC beams behavior are influenced by the dosage of cement. Adding nanoparticles leads to an increase of the shear strength. Nanoparticles and steel fibers show a negative interaction. Abstract: In the study herein presented, the influence of nanoparticles additions on the structural behavior of reinforced concrete beams is analyzed, in terms of both shear strength and bending moment capacity. For this purpose, concrete mixtures with additions of either silica nanoparticles (nano-SiO2 ) or aluminum nanoparticles (nano-Al2 O3 ) were produced. An experimental program was organized in two different sets: i) eight beams tested until shear failure was reached; and ii) eight beams tested until failure in bending was observed. These beams were produced with eight distinct concrete mixtures, with and without nanoparticles, and with and without steel fibers. Based on the data recorded, the following was analyzed: the force-displacement curve, the maximum strength in shear and in bending, the average curvature at critical cross-sections, the bending stiffness, the cracking pattern, and the failure type. It was concluded that the addition of nanoparticles, mainly nano-Al2 O3, to the concrete mixtures can lead to a strength increase, both in shear and in bending. It was also concluded that the interaction between the nanoparticles and the steel fibers can have a negative effect on the beams strength.