Exploratory Investigation of Nanomaterials to Improve Strength and Permeability of Concrete

Abstract

Concrete containing various supplementary cementitious materials (SCMs) such as silica fume, fly ash, and slag has improved properties. Nanomaterials, new SCMs with possible applications in concrete, have the smallest particle size (less than 100 nm). Nanomaterials are reactive because of the small size and large surface area of the particles, and they have great potential in improving concrete properties such as compressive strength and permeability. This study evaluates the use of a variety of nanomaterials in concrete compared with conventional concrete and concrete containing common SCMs. The potential benefits of using nanomaterials over other SCMs are high reactivity and cost-effectiveness; in addition, smaller amounts are necessary, resulting in less cement replacement. Concretes containing nanosilica and nanoclay were prepared in the laboratory. They were compared with concretes containing silica fume, fly ash, slag, or only portland cement. Specimens were tested for compressive strength and permeability. The microstructure of selected concretes with improved compressive strength and permeability was analyzed by using an atomic force microscope and nanoindenter to explain the improvements. The results of this study indicate that some of the nanomaterials tested have potential in concrete applications. The microstructure of the nanosilica concrete was denser and more uniform than the conventional concrete microstructure. In addition, the nanosilica had the largest improvement in both compressive strength and permeability among the nanomaterials tested.

Influence of Nanomaterials in Oilwell Cement Hydration and Mechanical Properties

“…These modifications and enhancements are attributed to factors such as densification, particle packing, acceleration, high surface area, increased nucleation sites, and structural reinforcement. This paper focuses on the influence of nanoparticles, specifically on the fresh and the hardened properties of the mixture (Senff et al 2010;Jalal et al 2012;Khaloo et al 2011;Leemann and Winnefeld 2007;Hosseini et al 2010;Ozyildirim and Zegetosky 2010;Gaitero et al 2010;Shih et al 2006;Ltifi et al 2011;Gaitero et al 2008). In particular, how nanosilica and nanoalumina can act as potential accelerators is investigated.…”

Study of durability of Portland cement mortars blended with silica nanoparticles

“…Zegetosky [39]. This must be added to a physical effect of filler as was claimed by Gaitero et al [21].…”

Application of nanoproppants for fracture conductivity improvement by reducing fluid loss and packing of micro-fractures

“…Use of nano-proppants prior to the placement of larger proppants will prevent fluid loss into the formation, increase the total extended length of the fracture network by propagating longer micro-fractures, and also increase the conductivity of those fissures and micro-sized fractures. Silica nanoparticles were found to show significant resistance against compressive stress, and have been used successfully in drilling fluids to decrease water invasion into shale formations (Cai et al, 2012;Ozyildrim and Zgetosky, 2010;Zou and Yang, 2006). Silica nanoparticles are very stable and do not coagulate at pH values above 8 (Zou and Yang, 2006) Additionally, silica nanoparticles will not show precipitation problems during the injection since they are very light.…”