材料期刊网

In this work, compressive, flexural and split tensile strength together with coefficient of water absorption of high performance self-compacting concrete containing different amount of Fe₂O₃ nanoparticles have been investigated. The strength and the water permeability of the specimens have been improved by adding Fe₂O₃ nanoparticles in the cement paste up to 4.0 wt%. Fe₂O₃ nanoparticle as a foreign nucleation site could accelerate C-S-H gel formation as a result of increased crystalline Ca(OH)₂ amount especially at the early age of hydration and hence increase the strength of the specimens. In addition, Fe₂O₃ nanoparticles are able to act as nanofillers and recover the pore structure of the specimens by decreasing harmful pores to improve the water permeability. Several empirical relations have been presented to predict the flexural and the split tensile strength of the specimens by means of the corresponding compressive strength at a certain age of curing. Accelerated peak appearance in conduction calorimetry tests, more weight loss in thermogravimetric analysis and more rapid appearance of peaks related to hydrated products in X-ray diffraction results indicate that Fe₂O₃ nanoparticles up to 4 wt% could improve the mechanical and the physical properties of the specimens.