Mechanical and Rheological Properties of Self-Compacting Concrete Containing Al2O3 Nanoparticles and Silica Fume

Abstract

In this paper, an experimental study of the mechanical and rheological properties of self-compacting concrete (SCC) containing Al2O3 nanoparticles (AL2O3 NPs) and silica fume (SF) has been investigated. In order to evaluate the fresh properties of concrete, Slump flow, V-funnel, and L-box tests have been conducted. The hardened concrete properties have been investigated using compressive and tensile strength tests. Also, water absorption of specimens has been evaluated using the water absorption test. Thirteen different amounts of AL2O3 NPs (0, 0.25, 0.5, 0.75, 1, 1.25, 1.5, 1.75, 2, 2.25, 2.5, 2.75, and 3%) as a substitute of cement were used. The amount of SF in all specimens is considered constant. According to the tests, the compressive strength of specimens containing 2.5% AL2O3 NPs as partial cement replacement after 7, 28, and 90 days is increased by 47, 88, and 86%, respectively. The reason for this enhancement is the reactivity of the AL2O3 NPs with Portland cement during the hydration process of cement. Also, the splitting tensile strength of specimens containing 2.5% AL2O3 NPs and 10% SF as partial cement replacement after 7, 28, and 90 days is increased by 29, 55, and 47%, respectively. On the other hand, the use of 1 and 2% of aluminum nanoparticles also reduced water absorption by 10% and 45%, respectively. In other words, the use of SCC in SCC containing silica fume has a positive effect and can be effective in cases where low water absorption is required.